The wreck of a Japanese prison ship that was sunk by U.S. warplanes and went down with more than 1,000 Allied prisoners of war in 1944 has been discovered in the Philippines.

The vessel was one of the notorious "hellships" used by the Japanese to ferry POWs between work camps. Many of the prisoners who died when the ship sank had worked on the infamous Burma-Thailand "Death Railway."

"Sadly, a lot of these prisoner transport ships were sunk by the Allies," expedition leader and American TV show host Josh Gates told Live Science. "The ships were painted to just look like military vessels, and they were inside the Japanese convoys — so the Allies thought they were legitimate military targets."

Gates teamed up with the Hellships Memorial Foundation, a U.S.-registered non-profit based in Subic Bay in the Philippines, to investigate the sinking of the hellship Hōfuku Maru. Its wreck had never been found, probably because searchers were guided by incorrect U.S. records to look too far north, he said.

But Japanese wartime records were more precise about the wreck's location, helping the team find the remains of the Hōfuku Maru in January, Gates said. His team has since made five dives to the wreck, which sits a few miles off the west coast of the main Philippines island of Luzon at a depth of about 160 feet (50 meters).

Prison ships

Japan used more than 130 hellships during World War II, but the wrecks of only a few have been found. Many hellships, including the Hōfuku Maru, were converted freighters. The Hōfuku Maru was used as a prison ship from 1942 until its sinking about two years later.

Gates said the vessel was part of a Japanese military convoy sailing from the Philippines to Japan when it was attacked on Sept. 21, 1944. U.S. warplanes had spotted the convoy, and one dropped a torpedo that cut the Hōfuku Maru in half. It quickly sank.

But the ship had roughly 1,200 Allied POWs on board, from the British and Dutch armies, many of whom had been forced to work on the Death Railway. Some were able to swim ashore, but they were recaptured by the Japanese. About 1,040 died in the sinking, Gates said.

War captives

The 1929 Geneva Convention placed strict limits on the use of prisoners of war for labor, but Japan was infamous for flouting these rules during World War II, claiming that it never ratified the convention and that wartime made POW labor important. Japan used POWs for slave labor on railways and docks, as well as in factories and mines. Of the roughly 132,100 prisoners captured from the United States and United Kingdom armies, nearly a third of them — about 35,000 people — died of exhaustion, malnutrition and disease.

Gates said the Japanese hellships used to ferry thousands of POWs between work camps were miserable places themselves: there was little light, air or food, and prisoners might be kept there for months. Human remains have been identified on the newfound wreck, and it will now be considered a war grave, he said. International conventions aim to prevent such wrecks from being disturbed.

The team first spotted the wreck with sonar, and then dove to identify parts of the structure that confirmed it as the Hōfuku Maru. They also mapped the wreck with a remotely operated underwater vehicle, which helped them determine that the ship had split into separate parts, just as accounts of the sinking had reported.

The Hellships Memorial Foundation would now work to try to locate the families of the victims, Gates said.

For the first time, shipwrecks associated with the real pirates of the Caribbean have been discovered in the Bahamas.

A team of archaeologists and filmmakers found six shipwrecks in and near Nassau, the capital of the island of New Providence. Three of the wrecks are linked to the "Golden Age of Piracy," according to a statement emailed to Live Science. One of them, found in Nassau's harbor, mostly consists of ballast stones, according to the team's report for the Bahamian antiquities authority. These stones were used to stabilize the ship, and they were found on top of the submerged remains of the ship's burnt wooden hull.

Attacking a vessel and pillaging its goods wasn't all these pirates did to their victims.

"After seizing a ship and taking its cargo, cannon and fittings, pirates had to get rid of all signs of their crime," Michael Pateman, director of the Bahamas Maritime Museum in Grand Bahama, said in the statement. "Burning ships to the waterline was an infamous tactic to hide felony from authorities. The Nassau hull shows all the signs of pirate mischief." The remains also include the ship's planks, frames and wooden treenails. The use of treenails, essentially wooden nails, indicate that the ship was built in the 1700s.

The Golden Age of Piracy was a brief but iconic time period from the 1680s to the 1720s marked by increased pirate activity in the Atlantic, as well as the Indian and Pacific oceans. It starred a significant number of notorious sea raiders. The port town of Nassau became the headquarters for the likes of Blackbeard, Calico Jack Rackham, Henry Avery, Benjamin Hornigold and Anne Bonny, among others.

At the height of the golden age in 1718, 40 shipwrecks burnt and sunk by pirates off Nassau’s shore were seen by Woodes Rogers, the governor of New Providence. But until now, none of these ships have been excavated. That changed when the crew received permission from the Antiquities, Monuments and Museum Corporation of the Bahamas to dive around Nassau, which they did in September and October 2025.

"Nassau harbour is huge," explorer and project filmmaker Chris Atkins said in the statement. "Tides flush dangerous currents through its waters twice a day. It's home to notorious packs of sharks. This was a risky expedition with high chances of finding nothing." But the team, aided by knowledge from local divers, were able to find six wrecks in all.

Another newfound golden age shipwreck — probably an early 18th-century armed sailboat with a single mast known as a sloop — is roughly 22 miles (35 kilometers) east of Nassau, and features a ballast pile, a large deck cannon and an iron swivel gun. The team also found a grinding stone for sharpening swords, lead musket balls and three cannonballs.

The presence war-related objects and the style of the swivel gun suggest that it was either a golden age pirate ship, or a sea vessel from that same time period with defenses against piracy, Sean Kingsley, marine archaeologist, co-director of the New Providence Pirates Expedition, and founder of the magazine Wreckwatch, confirmed to Live Science. The absence of cargo remains might make the pirate ship scenario more likely, however, he added.

The third shipwreck, which they spotted thanks to a tip, is beneath Nassau's old bridge, "where a very grumpy bull shark lives," according to the report. The site includes two poorly preserved hulls, one of which is pierced by a modern pipeline. Nonetheless, the team identified rigging, glass bottles, hull planks and cooking galley bricks, Kingsley said in the statement. The ship probably sank after striking an underwater sandbank in a storm, he told Live Science in an email.

Furthermore, the diving team found the remains of shipping containers and dozens of clay tobacco pipes bearing the British coat of arms. They were probably made in London in the 1740s or 1750s. The ship was likely also English and traveled to New Providence shortly after the pirates were no longer a threat, when Nassau was transitioning to a pirate-free life.

In addition to hunting for shipwrecks, the team wanted to understand life in this pirate capital. When they weren't diving, they were studying old maps and 300-year-old documents and investigating pirate caves, a plantation with enslaved people, and a lookout tower where it's rumored Blackbeard once lived. Unsurprisingly, Nassau in the Golden Age of Piracy was "nothing like the Hollywood fantasy," Kingsley said. "Nassau's Piratetown was more like a combination of a cowboy frontier town meets an 18th-century holiday camp."

The team's members come from the New Providence Pirates Expedition and Wreckwatch TV, and they are the first to have ever received diving permission in the closed zone of Nassau harbor. Kingsley and Chris Atkins, Wreckwatch TV co-founder, have produced a Wreckwatch TV documentary series about the findings. Wreckwatch Magazine will also share the New Providence Pirates Expedition's preliminary outcomes.

"It might have been a short life, but for a brief period of mayhem, sailors found freedom and wealth unmatched anywhere on earth," Pateman said. "That escape was the pirate dream."

Nearly 180 years after they died of cold and starvation in the Canadian Arctic, four crewmembers who perished in the Franklin expedition have been identified thanks to genetic analyses that matched their DNA with that of living descendants.

Three of the victims were from HMS Erebus, one of the expedition's two vessels, and died at Erebus Bay, the researchers reported in a new study published Wednesday (May 6) in the Journal of Archaeological Science: Reports. The fourth victim, a captain on HMS Terror, is the first from that ship to be identified with DNA, according to a second study that was published Thursday (May 7) in the journal Polar Record.

The findings reveal that "none of the men [from HMS Erebus] were alone when they died," the researchers wrote in the first of those studies, adding that "it is our hope that additional identifications can be made to provide that kind of information to other descendants." Based on the location of the bodies, researchers believe that other survivors were still alive and nearby.

The Franklin expedition departed England in May 1845, with an aim of discovering a Northwest Passage, an Arctic route to connect the Atlantic and Pacific oceans. Sir John Franklin commanded the mission's two ships. However, the ships and their 129 crewmembers became stuck in ice off a Canadian archipelago in late 1846, and Franklin died June 11, 1847.

On April 22, 1848, the surviving 105 crewmembers left the ships off King William Island and tried to make it to the Canadian mainland, walking and dragging boats on sleds, but all of them died along the way.

Search expeditions launched over the following two decades found some human remains and artifacts, as did scientific expeditions launched in the 20th and 21st centuries, which finally led to the discovery of the long-lost ships.

The new DNA analysis sheds light on exactly where each ship's crew traveled in their doomed attempt to find safety. One victim, Harry Peglar, was "Captain of the Foretop on HMS Terror," the team found in their research. Papers belonging to Peglar were found on another man's body in 1859 and include poetry and descriptions of events on board the ships.

Peglar's remains were discovered about 125 miles (200 kilometers) from the frozen ships, meaning he had made it far into the remote wilderness. "What is known is that he died alone, dressed in the uniform of a steward," the researchers wrote in the Polar Record study.

The other three newly identified individuals are William Orren, an able seaman on HMS Erebus; David Young, a boy first class on HMS Erebus; and John Bridgens, a subordinate officer's steward on HMS Erebus.

According to historical records, Orren first went to sea in 1821, when he was just 15 years old. He served on HMS Swan in 1830 and HMS Alfred in 1831. "He wouldn't sail with the navy again for another 14 years, until he joined the crew of HMS Erebus in Woolwich on 19 March 1845 as an Able Seaman when he was 38 years old," the team wrote in the first study.

Historical records also say Orren was about 5 feet, 4 inches (1.63 meters) tall, with dark hair, a light complexion and brown eyes. A descendant of his sister provided the DNA that allowed him to be identified.

Young was 17 years old when he joined HMS Erebus. His father was also a navy sailor but wasn't posted to the Erebus expedition. The DNA used to identify him came from a descendant of one of his brothers.

Bridgens was born in 1818, and his father was a sailor who never married his mother. Bridgens was trained by his stepfather to be a hairdresser, but he went to sea instead. Records indicate that he first went to sea as a musician in 1829. He served aboard HMS Endymion in 1841, during a war with China, and "volunteered for the Franklin expedition in Woolwich on 20 March 1845, when he was 26 years old," the team wrote in the article. The DNA of a descendant of one of his half-sisters was used to identify the remains of Bridgens.

"He was 5 ft 6 inches [1.68 m] tall, with dark hair and hazel eyes," the researchers wrote in the study. "His seaman's ticket indicates that he was illiterate, which is further demonstrated by his marking his name with a cross on his allotment records."

Previous DNA studies identified other members of the Franklin expedition, including John Gregory, an engineer on the Erebus, and James Fitzjames, who became captain of the Erebus after Franklin's death and was likely cannibalized.

"For the living descendants, these findings provide previously unavailable details regarding the circumstances and locations of their relatives' deaths, as well as the identities of some of the shipmates who died with them," Douglas Stenton, an anthropologist at the University of Waterloo in Ontario and first author of the Journal of Archaeological Science: Reports paper, said in a statement.

The team's work continues, and the remains of more crewmembers may be identified.

A marble fragment from the Acropolis of Athens has been found in the remains of a ship that sank in 1802, according to Greece's Ministry of Culture.

The ship is the Mentor, a brig that went down southeast of the island of Kythira (also spelled Cythera and Kythera) in the Aegean Sea. The ship was used by Thomas Bruce, the seventh Earl of Elgin, to move sculptures from the ruins of the Acropolis to the United Kingdom, Greece's Ministry of Culture said in a translated statement.

The Acropolis is a high-ground area in Athens that contains some of the city's most important buildings ‪—‬ most notably, the Parthenon, a temple dedicated to Athena, the patron goddess of the city. The sculptures that Lord Elgin was removing depict scenes from Greek mythology, especially the birth of Athena. It's not certain if the newly found fragment is from the Parthenon itself or from elsewhere on the Acropolis.

After the ship sank, Elgin had sponge divers dive down to the wreck. They salvaged many of the sculptures, which were sold to the British Museum in 1816, where they remain to the present day.

Modern-day archaeologists have been excavating the remains of the ship since 2009. The ship itself is mostly disintegrated, but remains from the 19th century, such as a chess set, have been found. The most recent excavations found remains of the ship's copper plating and of a clay hearth that would have been used by the ship's crewmembers.

The ancient sculpture found in the ship is a triangular, marble block with what looks like a peg at the bottom. Modern-day scholars refer to pieces like this as a "drop," Greek Ministry of Culture representatives said in the statement. It's about 3.7 inches by 1.9 inches (9.3 by 4.7 cm) in size and would have been attached to other blocks somewhere in the Acropolis, possibly on the Parthenon itself.

At the time Lord Elgin was removing the sculptures, now known as the Elgin Marbles or the Parthenon Marbles, Greece was under the control of the Ottoman Empire. Elgin claimed that he was given proper authorization from Ottoman officials to move the sculptures. Greece has requested the return of the sculptures from the British Museum, claiming that Elgin did not have the required permission and noting that Greece was being occupied by the Ottoman Empire at the time.

The museum has refused, but starting in 2021, the museum reportedly had talks about returning the Elgin Marbles to the Greek government. So far, an agreement has not been reached. One challenge is that the laws of the United Kingdom prevent the British Museum from deaccessioning any artifacts. This makes it more difficult to return them to Greece.

Conservation and analysis of the recently discovered remains from the shipwreck are ongoing.

A sea raiders' boat that sank off the coast of Denmark 2,400 years ago has been hiding a fingerprint, as well as several chemical clues that are now helping researchers uncover just where these raiders came from millennia ago, a new study finds.

The vessel, known as the Hjortspring boat, is the oldest known wooden plank boat in Scandinavia, and is currently on display at the National Museum of Denmark. But its origins have long been an enigma.

"Where these sea raiders might have come from, and why they attacked the island of Als has long been a mystery," Mikael Fauvelle, an archaeologist at Lund University who analyzed the boat, said in a statement.

About 2,400 years ago, about 80 sea raiders on an armada including this boat and three others attacked the island of Als, off the coast of what is now Denmark. But the raiders lost. In giving thanks for their victory, the people on Als sank the boat as an offering along with the attackers' weapons and shields.

The sinking of the boat in the fourth century B.C. helped preserve it over the centuries, as water is a low-oxygen environment. After its discovery in the 1880s, the boat was later excavated from the bog of Hjortspring Mose in the 1920s (earning the ship its name).

"But at the time, we lacked the modern scientific methods that we needed to answer the mystery of where these attackers came from," Fauvelle said in a video about the research.

Recently, the researchers decided to take a fresh look at the boat. Before it was put on display in the museum, the boat had been chemically preserved. So, the team sifted through archives and old records in multiple museums in an effort to uncover parts of the boat that had been left untouched.

Finally, they found several fragments of caulking tar and rope, including a piece of tar that had the ancient fingerprint of someone who likely helped repair the vessel, a finding that Fauvelle called "really fantastic."

"This remarkable fingerprint provides a direct link to the ancient seafarers who used this boat," the researchers wrote in the study, which was published on Dec. 10 in the Journal PLOS One.

To study the caulking tar, the researchers used gas chromatography and mass spectrometry, techniques that examine the chemical makeup of samples. They found that the waterproof tar was a mixture of animal fat (likely tallow) and pine pitch, a sticky and stretchy substance also known as resin.

"This suggests the boat was built somewhere with abundant pine forests," Fauvelle said in the statement.

The new finding throws cold water on an old idea that the boat originated near modern-day Hamburg, Germany, as previous analyses had found that the vessel carried wood containers that looked like ceramics from the Hamburg region. It now appears that the boat may have come from much farther away in the Baltic Sea region, which has pine forests.

"Pine forests only existed in certain parts of northern Europe at this time," Fauvelle said in the video, adding "we suggest that they came from somewhere along the coast of the Baltic to the east of the modern day island of Rügen [in Germany]."

If this idea is accurate, it suggests that the attackers sailed a great distance over open sea for the raid, Fauvelle said.

Researchers also used carbon dating to study rope from the boat. Analyzing the lime bast cordage, which comes from the inner bark of trees, the team confirmed the boat's previously determined timeline of between 400 B.C. and 101 B.C., which falls in the pre-Roman Iron Age of Scandinavia. The researchers carbon dated the boat to between 381 and 161 B.C., which is the first direct date from the boat's material. The researchers also worked with rope makers to create replicas of the cordage and study the rope-making process.

Using X-ray tomography to scan the caulking and cordage in sections, the team made digital 3D models, which enabled them to study the fingerprint. Analyzing the print's ridges didn't narrow down the sex or identity of who made the print, however.

Going forward, Fauvelle hopes to extract human DNA from the tar to learn more about the people who made and used the boat. Understanding faraway raids such as this one could help explain ancient maritime warfare and Iron Age trading systems.

While diving off the coast of Egypt, underwater archaeologists found the 2,000-year-old remains of a boat that may have been a luxurious "pleasure barge" for the ancient elite.

The team discovered the barge in the ancient harbor of Alexandria, the capital of Egypt during the Ptolemaic period (304 to 30 B.C.) and a major city when the Roman Empire later dominated the region.

The wreck consists of several well-preserved timbers, about 90 feet (28 meters) long, from a barge that had been about 115 feet (35 m) long and 22 feet (7 m) wide, according to a statement from French underwater archaeologist Franck Goddio. He thinks it was a "thalamagos" (also spelled "thalamegos"), a Greek word that literally means "cabin carrier" and was used to describe Ptolemaic Egypt's floating palaces.

Goddio said his team discovered the remains of the vessel in October, during underwater excavations of now-sunken ruins of a Temple of Isis. The temple once sat on the island of Antirhodos, which now lies underwater, and was within the "Portus Magnus," or Great Harbor, used at Alexandria during the Ptolemaic period. The temple there was destroyed, probably during an earthquake in about A.D. 50, and the island sank beneath the waves between the fourth and the eighth centuries.

Goddio thinks the pleasure barge would have carried a luxuriously decorated central cabin and been propelled by oars. No remains of such a vessel have ever been found, although they were described by ancient writers and portrayed in Egyptian art.

Among the lotuses

Giant pleasure barges were popular during the Ptolemaic dynasty in Egypt and were described by the first-century-B.C. Greek geographer Strabo as ferrying the wealthy between choice spots: "… they hold feasts in cabin-boats in which they enter the thick of the cyami [Egyptian lotuses that grow in fresh water] and the shade of the leaves."

In Strabo's time, Alexandria was under direct Roman control — an ancient regime change that began at the Battle of Actium in 31 B.C., when naval forces commanded by Roman leader Octavian (later Augustus) defeated the navy of Cleopatra VII (the last ruler of the Ptolemaic dynasty) and her lover, the Roman rebel Mark Antony.

Exactly how the newfound vessel ended up by the island of Antirhodos is unclear.

"This intriguing shipwreck could have been used along the canals in Alexandria as Strabo described," Goddio said in the statement. But it was found near the underwater ruins of the Temple of Isis on Antirhodos and may have been caught up in the destruction there.

As a result, the researchers suggested "a ritual use for this barge," Goddio said. It may have been part of the "navigatio iside," a naval ceremony held in Roman-era Alexandria when a procession celebrating Isis carried a richly decorated vessel called the "Navigium" through the streets. The mock-up boat represented the solar barque that the Egyptian gods used to navigate across the heavens. (Isis was the goddess of the sea.)

That, in turn, could mean that "this vessel was performing a yearly ritual voyage of the goddess from the Portus Magnus of Alexandria to the sanctuary of Osiris at Canopus, alongside the Canopic Channel" of the Nile, Goddio said.

Early Roman Egypt

The research into the wrecked vessel is at a very early stage, but it "promises to be a fascinating journey into life, religion, luxury and pleasure on the waterways of early Roman Egypt," Goddio said.

The vessel is a "spectacular find," said Timmy Gambin, a maritime archaeologist at the University of Malta whose research covers ancient vessels as well as wartime wrecks. However, it has not yet been scientifically determined if the vessel is actually a thalamagos, said Gambin, who was not involved in the discovery.

"It is yet early days to determine exactly what the vessel was used for," he told Live Science in an email.

Divers have recovered over 1,000 coins from a shipwreck off the east coast of Florida. The coins were discovered this summer within the historical "Treasure Fleet" of Spanish ships that sank in July 1715, when hundreds of sailors and over $400 million worth of gold and silver disappeared into the ocean.

In a statement, representatives for 1715 Fleet - Queens Jewels, a shipwreck salvage company authorized to dive to the wrecks, wrote that they had recovered more than 1,000 silver reales (also called "pieces of eight") and five gold escudos, along with other rare gold artifacts. Both types of coin were common currency in the Spanish colonies in the Americas.

"Each coin is a piece of history, a tangible link to the people who lived, worked, and sailed during the Golden Age of the Spanish Empire," Sal Guttuso, director of operations for 1715 Fleet - Queens Jewels, said in the statement. "Finding 1,000 of them in a single recovery is both rare and extraordinary."

The coins were most likely minted in the Spanish colonies of Mexico, Peru and Bolivia, according to the statement. Some have mint marks and visible dates, and their excellent condition suggests that they were part of a single collection that spilled and were quickly buried when one of the ships broke apart.

The 1715 fleet, also known as the "Plate Fleet," had been loaded with coins and other products from Spanish colonies, and the 12 ships set sail from Cuba on their annual trip back to Spain on July 24. After a few days of sailing, the fleet encountered an intense hurricane off the east coast of Florida. Eleven ships sank, and their remains were scattered over a span of 50 miles (80 kilometers). Some of the treasure was recovered soon after the disaster, but much of it remained under the ocean for centuries.

"Every find helps piece together the human story of the 1715 fleet," Guttuso said. The coins will be conserved and displayed to the public at local museums, according to the statement.

Exploration of the 1715 shipwrecks has produced other impressive finds over the past decade. In 2015, divers found an extremely rare Spanish coin called a "tricentennial royal" that had been minted for King Philip V of Spain, along with nearly $1 million worth of gold coins and gold chains. But that team, headed by Eric Schmitt of Booty Salvage, failed to report 50 coins they found in the shipwreck. Local authorities working with the FBI managed to recover most of the stolen coins in 2024.

Various treasures from the wrecked fleet are likely still hidden under the ocean. The fleet was said to be carrying jewels belonging to Philip V's second wife as part of her dowry, including a 74-carat emerald ring and 14-carat pearl earrings.

Under Florida law, removal of artifacts from shipwrecks is illegal unless a permit is secured. 1715 Fleet - Queens Jewels has exclusive rights to dive at the wrecks.

Archaeologists have discovered four 18th-century shipwrecks off the coast of North Carolina, including what may be the wreck of La Fortuna, a Spanish privateer from Cuba that exploded during an attack in 1748.

The wrecks were found near Brunswick Town, a major Colonial port on the southern coast of North Carolina. The town was the first successful European settlement of the Cape Fear region (named due to 16th-century sailors' fears of getting shipwrecked), and the port was used to export pine products like tar and turpentine used by the Royal Navy. But archaeologists surveying the area had not expected to find such a large number of wrecks and colonial artifacts.

"Visibility [underwater] is consistently pretty low in the Cape Fear River," Cory van Hees, a graduate student at East Carolina University (ECU), said in a statement. Van Hees got disoriented while diving and came across beams of wood sticking out of the mud. "I didn't understand what I was looking at in that moment," van Hees said, "but I knew I should relay the wooden structure to faculty."

The project co-leaders, ECU maritime archaeologists Jason Raupp and Jeremy Borrelli, think one of the wrecks, which comprises 47 timbers, is La Fortuna. Historical records note that two Spanish ships anchored off Brunswick Town on Sept. 4, 1748. The Spanish began to raid the then-English town, but they were surprised by a counterattack from the colonists a couple of days later. During the attack, La Fortuna exploded and sank.

The project team found two major clues that the wreck is indeed La Fortuna: the timbers and the artifacts nearby, including Spanish pottery.

Some of the wood used in the ship's construction was from a cypress species native to Central America. This suggests that shipbuilders used raw materials from a Spanish Caribbean colony to construct the ship, according to the statement, and La Fortuna is the only Spanish ship known to have sunk in this area.

Related: Coins worth over $1 million recovered from 1715 Spanish treasure shipwrecks in Florida

While recording the shipwrecks this summer, the team "found hundreds of artifacts," Borrelli told Live Science in an email, including "ceramic sherds, glass container bottles, clay tobacco pipes, a cooper's adze [cutting tool], barrel heads and staves, sailcloth, leather shoes, possible clothing fragments, and butchered animal bone." In addition, two fragments of 18th-century Spanish-American ceramics are "another clue supporting the preliminary identification of La Fortuna," Borrelli said.

The other three wrecks are still something of a mystery. All of them have construction details and artifacts that suggest they were used in the 1700s, Borrelli said, which means the wrecks are likely associated with the 50-year lifespan of the Colonial port at Brunswick Town. But coastal erosion has dramatically impacted the archaeological site, scattering the shipwrecks' remains over a wide area, he said.

Raupp and Borrelli plan to continue their investigation into the wrecks.

"As we dig deeper and uncover more evidence, it may lead us in another direction," Borrelli said. "It is highly improbable that any of the other shipwrecks found at Brunswick Town are Spanish vessels, but we can't rule anything out at the moment."

Archaeologists say they've found the submerged wreck of a sailing ship captured in 1721 near Madagascar, during one of history's most infamous pirate raids.

The American researchers, from the Center for Historic Shipwreck Preservation, have investigated the wreck for 16 years and now think it's the remains of Nossa Senhora do Cabo, a Portuguese ship carrying cargo from India that was attacked and seized by pirates, among them the notorious pirate captain Olivier "The Buzzard" Levasseur.

The wreck now lies on the floor of a small harbor on the island of Nosy Boraha off the northeast coast of Madagascar, which was a hangout known as Île Sainte-Marie during the "Golden Age of Piracy" in the early 18th century. New details of the investigations have been published in the latest issue of Wreckwatch magazine.

The identification of the wreck is "supported by multiple lines of evidence," the center's co-founder and director Brandon Clifford, one of the researchers, told Live Science in an email. These include analysis of the structure of the ship from its underwater remains, historical records and artifacts found in the wreckage.

Among them are devotional figurines and objects made from wood and ivory, including one that depicts Jesus' mother Mary; part of a crucifix; and an ivory plaque inscribed with gold letters that read "INRI." (According to the Christian gospels, these letters were inscribed by the Romans above the crucified Jesus and stood for "Jesus of Nazareth, King of the Jews" in Latin.)

The researchers think these artifacts were made in Goa, which was then the center of a Portuguese colony on India's west coast, and were being shipped to Lisbon in Portugal.

Related: 'Pirate' shipwrecks that sank in 1710 off Costa Rica are actually remains of Danish slave ships

Pirate raid

According to records, Nossa Senhora do Cabo (Portuguese for "Our Lady of the Cape") had left Goa early in 1721 bound for Lisbon, with the outgoing Portuguese viceroy and the Archbishop of Goa both on board.

But the vessel was attacked and captured by a group of pirate ships on April 8, 1721, near the French island of La Réunion (also known as Réunion Island) in the Indian Ocean.

The treasure it carried included ingots of gold and chests full of pearls, according to the researcher Denis Piat in his book "Pirates & Privateers in Mauritius" (Didier Millet, 2014).

Clifford and his colleague Mark Agostini, an archaeologist at Brown University, said the Portuguese ship had already been badly damaged in a storm and had jettisoned most of its cannons to stay afloat; and so it was captured with little resistance.

The viceroy was eventually ransomed, but it's not known what became of the archbishop. About 200 enslaved people from Mozambique below decks, but there are no records of what happened to them.

According to Clifford and Agostini, the entire haul was "an eyewatering treasure, even by pirate standards," and the cargo alone may have been worth more than $138 million in today's money.

Sea dog base

The pirates then steered their captured prize toward Madagascar, about 400 miles (650 kilometers) west of La Réunion, to divide up their loot.

The researchers wrote that Île Sainte-Marie was chosen by European pirates because its sheltered anchorages were close to major shipping lanes. It was also known for its "absence of colonial governance," making it an ideal pirate base.

Clifford added that between seven and 10 shipwrecks were wrecked or scuttled near Île Sainte-Marie during the Golden Age of Piracy and "at least four pirate shipwrecks or their prizes lie in the harbor itself."

Agostini, meanwhile, told Live Science in an email that more than 3,300 artifacts had now been recovered from the wreck of Nossa Senhora do Cabo, but that the overlying silt and sand had made further recoveries difficult.

He added that archaeologists had previously overlooked Île Sainte-Marie and the scientific treasures it contained. "Ideally, future fieldwork will lead to more analysis of the many wrecks there," Agostini said.

Editor's note: This story was updated at 2:32 p.m. ET to remove a detail about a gold- and ruby-encrusted cross being on the ship at the time of its capture. This cross was mentioned in a book about the shipwreck, but Live Science has since learned that it might be a myth.

Centuries-old shipwrecks off the coast of Costa Rica, long thought to have been the property of pirates, are actually Danish ships that took part in the 18th-century transatlantic slave trade, new research reveals.

The two shipwrecks sit in the shallow waters off the coast of Cahuita National Park in southern Costa Rica and have been known about for decades. But a chance find of unique yellow bricks near one of the wrecks, followed by a more in-depth investigation of the ships' contents and wood, enabled marine archaeologists from Denmark to confirm that the wrecks were actually 18th-century Danish slave ships.

These shipwrecks are now thought to be the remains of the Fridericus Quartus and Christianus Quintus, which disappeared off the coast of Central America in 1710, and until now, had never been found.

"It's been a long process and I've come close to giving up along the way, but this is undoubtedly the craziest archaeological excavation I've yet been part of," Andreas Kallmeyer Bloch, a marine archaeologist and museum curator at the National Museum of Denmark, said in a statement. "Not only because it matters greatly to the local population, but also because it's one of the most dramatic shipwrecks in the history of Denmark, and now we know exactly where it happened."

The Fridericus Quartus and Christianus Quintus were large ships used by the Danish West India Company, which operated Denmark's transatlantic slave trade between West Africa, the Danish West Indies (including the modern-day islands of St. Thomas, St. Jan and St. Croix), and Denmark. Though smaller in scale compared to the British, French or Portuguese empires, Denmark was an active participant in the transatlantic slave trade from the mid-1600s until the early 1800s, according to the Digital Encyclopedia of European History. More than 120,000 enslaved Africans were transported by the Danish West India Company alone.

Related: Plantation slavery was invented on this tiny African island, according to archaeologists

According to the National Museum of Denmark, historical sources state that both of the ships sank in 1710. As the Fridericus Quartus was preparing to leave Ghana, the enslaved people broke out of their shackles and rebelled. But the rebellion failed and the ship's crew cut off their leader's hands and then decapitated him. To protect against further unrest, the Christianus Quintus accompanied the Fridericus Quartus, bringing the total number of people on both ships to 800. But they got lost on their way to the Dutch colony of St. Thomas and were running low on food. The crew threatened mutiny, demanding the enslaved people be released so the crew could divide the ship's remaining food among themselves.

The captains agreed, and around 600 enslaved people ended up on the shores of Costa Rica, after which the Fridericus Quartus is thought to have caught fire. The Christianus Quintus, meanwhile, had its anchor rope cut and was promptly smashed to pieces by the waves. However, the exact site of the wrecks remained unknown.

Yellow bricks

The two wrecks off the coast of Costa Rica had long been known to locals, and were assumed to be pirate ships due to their broken-up state, suggesting that they may have sunk after battling one another. However, this assumption was challenged in 2015 after archaeologists found yellow bricks in one of the ship's remains.

The clay from this yellow brick was analyzed, leading to its identification as a Flensburg brick. These bricks were used almost exclusively in Denmark and its colonies, and were only made in very particular places in Denmark.

Now, after a subsequent underwater excavation in 2023, the National Museum of Denmark has now revealed their findings.

"The analyses are very convincing and we no longer have any doubts that these are the wrecks of the two Danish slave ships," David Gregory, a marine archaeologist and research professor at the National Museum of Denmark, said in the statement.

During the expedition, marine archaeologists from the National Museum of Denmark and the Viking Ship Museum dove to the shipwrecks and took samples of wood, bricks and several clay pipes that they discovered.

Scientists performed dendrochronological analyses, also known as tree-ring dating, on the wood samples from the ships, which showed that they were made from oak timber that had originated in the western Baltic, specifically northeastern Germany, Denmark or Sweden. Additionally, the wood was confirmed to have been from a tree that was cut down between 1690 and 1695, and showed signs of being burned before the ship sank, consistent with historical reports of the ships having caught fire.

The brick samples were also analysed, which showed that they were indeed Flensburg bricks and had been manufactured in either Iller Strand or Egernsund, both hubs of 18th-century brick production situated near Flensburg Fjord.

Additionally, the clay pipes were identified as having been produced by the Dutch just before 1710, when the Fridericus Quartus and Christianus Quintus sank. These pipes were often used by Danish sailors, and were also not generally used for more than five years.

"The bricks are Danish and the same goes for the timbers, which are additionally charred and sooty from a fire," Gregory said. "This fits perfectly with the historical accounts stating that one of the ships burnt."

The mysterious Antikythera Mechanism may not have been a cryptic celestial measuring device, but just a toy prone to constant jamming. And the secret to its true purpose, according to new research, is its triangle-shaped teeth.

Discovered in a shipwreck in 1901, the Antikythera Mechanism has remained an enigma for more than a century. Several years ago, CT scans suggested that the 2,000-year-old device was an astronomical tool.

Consisting of a hand crank, many interlocking gears and various indicators, the Mechanism could seemingly perform many tasks. These include giving the date according to the Egyptian and Greek calendars, displaying the positions of the sun, moon and planets within the zodiac, and predicting future lunar and solar eclipses.

But was celestial measurement really the purpose of this fascinating device? Was it meant to be a powerful computer, or a simple toy? And was it a one-off, made for a wealthy patron, or just one example of a mass-produced tool?

For decades, researchers have attempted to understand how accurate the Mechanism is, as that would help resolve its intended purpose. If it wasn't very accurate, for example, then it might have been a toy or an educational model. But if it was incredibly precise, it might have been used by court astrologers to make forecasts and horoscopes.

Related: Antikythera mechanism, world's oldest computer, followed Greek lunar calendar

Unfortunately, the Antikythera Mechanism spent more than two millennia buried at the bottom of the sea, and an unknown amount of time functioning before that. Its gears are highly corroded, and many parts are missing.

Triangles point the way

In the new study, submitted April 1 to the preprint server arXiv, Argentinian scientists created a computer simulation that replicated the Antikythera Mechanism's movements. This simulation incorporated errors from the imprecise nature of its manufacture, where the gears didn't have exact spacing between them.

Crucially, unlike previous efforts to recreate the Mechanism, the researchers also included an accurate model of the Mechanism's triangle-shaped gear teeth, which affect how well gears interlock with one another, and how well the indicators point to the intended astronomical target.

From this model, the researchers found that the Mechanism wasn't very useful at all. It could only be cranked to about four months into the future before it inevitably jammed, or its gears simply disengaged. The user would then have had to reset everything to get it going again — similar to trying to fix a modern printer. Considering that the indicators marking the date cover an entire year, this jamming problem seems unfortunate.

One possibility is that the Antikythera Mechanism was a fancy toy that was never intended to be fully accurate, or that it came with an instruction manual that required users to reset it after a few turns — much like a mechanical watch whose mainspring must be occasionally adjusted by hand.

But given the obvious craftmanship that went into creating such a complex device, the researchers don't believe that the Mechanism was just a janky toy. After all, if it was never intended to be accurate, detailed or forward-looking, why bother putting in all that hard work in the first place?

Another possibility, which the researchers think is more likely, is that current measurements of the gears and teeth are off. CT scans can only provide a certain level of resolution, and two thousand years of corrosion may have warped or distorted the components far beyond their original state. The Mechanism's original creators may have made it precise enough to avoid jamming and still provide reliable predictions for years into the future.

Either way, the Antikythera Mechanism represents the apex of ancient engineering expertise. And despite modern technology and tools such as CT scans, its ultimate purpose may stay forever mysterious.

A 15th-century shipwreck off the coast of Sweden may be Scandinavia's oldest shipwreck built in the innovative "carvel" style — a design that gave it the strength to carry heavy cannons, archaeologists say.

The wreck at Landfjärden, south of Stockholm, is one of five in the area that have been known since the 1800s. They were commonly thought to have been from ships dating to the Viking Age (A.D. 793 to 1066).

But last year, maritime archaeologists at Vrak, the museum of wrecks in Stockholm, revealed that four of the wrecks date to the 1600s and 1700s and that the oldest wreck was built before 1480 and perhaps as early as the 1460s, museum curator and project manager Håkan Altrock said in a statement.

"It's a large ship, likely about 35 metres [115 feet] long and 10 metres [33 feet] wide," he said. "The ship's frame still rises high above the seabed, and in the stern, both the sternpost and rudder remain upright."

Related: 32 haunting shipwrecks from the ancient world

New shipbuilding technique

The most significant aspect of the wreck, now known as "Vrak 5," is that it was built in the "carvel" style, with planks on the hull that were flush with neighboring planks so that the whole hull surface was relatively smooth, Altrock said.

By contrast, traditional Nordic ships, such as Viking longships, were built in the "clinker" style with overlapping planks, which had made them light and relatively flexible.

But the use of carvel-style flush planks — an innovation from the Mediterranean dating to about the seventh century A.D. — meant that a ship's hull could be reinforced with framing to make it stronger. This was an important consideration when ships started carrying cannons in the 15th century, Altrock said, so traditional "clinker-built" ships soon became obsolete.

Important wreck

These details make Vrak 5 key to understanding the transition from clinker-built to carvel-built ships — an important period in Sweden's maritime history, Altrock said.

"We plan to apply for external funding for an excavation," he said. "This ship represents a fascinating link between medieval and modern shipbuilding."

The new analysis also showed that the trees used for the wood in Vrak 5 had been felled in Sweden's southern Kalmar region or in the nearby Blekinge region, Altrock said.

The Vrak archaeologists have also made a digital model of the wreck using photogrammetry — a technique that combines digital photographs so that their positions are reflected in three dimensions — and the results are now online.

Authorities have recovered 37 gold coins stolen from several 18th-century shipwrecks off the coast of Florida. The collection — part of a trove of over 100 coins initially discovered in 2015 — is valued at over $1 million.

According to the Florida Fish and Wildlife Conservation Commission (FWC), salvage operators contracted to investigate Spanish shipwrecks near Vero Beach, reported half the historic coins they found and illegally withheld information about the other half.

The historical wrecks were laden with treasure, as the Spanish were carrying gold and silver from the "New World" to Spain to help pay for the country's costly wars, according to the 1715 Fleet Society, a Pennsylvania-based nonprofit that researches the fleet.

On July 24, 1715, the fleet of Spanish treasure ships left Havana, Cuba, headed to Spain. When the fleet ran into a hurricane off the east coast of Florida days later, 11 of the 12 ships sank. Hundreds of sailors died and over $400 million worth of gold and silver went down with the ships.

Three centuries later, members of the Schmitt family, contracted to salvage artifacts from the shipwrecks, made headlines when they announced they had found 51 gold coins and 40 feet (12.2 meters) of gold chain worth over $1 million.

The Schmitts, however, did not disclose the other 50 coins they found.

Related: Which Is Rarer: Gold or Diamonds?

FWC investigators worked with the FBI to figure out that Eric Schmitt, who worked for his family's company, the Fort Pierce-based Booty Salvage Inc., planted three of the purloined gold coins on the ocean floor in 2016 so that investors could find them. Schmitt also sold several of the coins between 2023 and 2024 to auction houses and private individuals, according to an FWC statement .

In all, FWC has recovered 37 of the 50 coins that the Schmitts stole from the 1715 Fleet shipwrecks.

"This case underscores the importance of safeguarding Florida's rich cultural heritage and holding accountable those who seek to profit from its exploitation," FWC Investigator Camille Soverel said in the statement.

The recovered coins will now be returned to their rightful custodians, according to FWC. Investigators continue to pursue recovery of the remaining 13 stolen coins.

A wreck off the coast of Kenya may have been a ship from one of Vasco da Gama's pioneering voyages into the Indian Ocean 500 years ago, archaeologists say.

The remains of the vessel, which were discovered near the Kenyan town of Malindi in 2013, are among eight known Portuguese shipwrecks from this period in the area. Researchers think it may be the São Jorge, which sank in 1524, although the identification is not certain.

If the wreck is the São Jorge, it may be one of the earliest European shipwrecks in the Indian Ocean, but "we don't know for sure," Filipe Castro, a maritime archaeologist at the University of Coimbra in Portugal and lead author of a new study describing the recent work, told Live Science.

According to the study, published Nov. 18 in the Journal of Maritime Archaeology, Castro and his colleagues now hope to verify their identification, in part by conducting an archaeological survey of the coral reefs that stretch north from Malindi to Ras Ngomeni, Kenya — a distance of about 15 miles (25 kilometers).

Related: 32 haunting shipwrecks from the ancient world

The wreck lies about 1,640 feet (500 meters) from the shore, at a depth of about 20 feet (6 meters). Little of it can be seen amid corals on the seabed, but Castro and other divers unearthed timbers from the ship's hull and frame in two archaeological trenches they made at the submerged site.

Portugal to India

Da Gama (lived circa 1469 to 1524) pioneered the route from Europe into the Indian Ocean in 1497, when his ship was the first to round the Cape of Good Hope at the southern tip of Africa. The Portuguese explorer made three more journeys along the route before his death in India in 1524, possibly from malaria, and his explorations were the basis of the Portuguese trading empire in the Indian Ocean.

The São Jorge was one of about 20 ships that joined da Gama for his final voyage in 1524, but it sank shortly before his death. The new study suggests it was one of two early Portuguese ships that sank near Malindi; the other was Nossa Senhora da Graça, which went down in 1544.

If the wreck near Malindi can be confirmed as the São Jorge, it would have "significant historical and symbolic value as physical testimony to the presence of Vasco da Gama's third armada in Kenyan waters," Castro said in a statement earlier this year.

"I think this is a unique shipwreck," he told Live Science. "It is a treasure."

Mystery wreck

Kenyan authorities were interested in the Malindi shipwreck, Castro said, and the site may be developed as an underwater museum.

The wreck was discovered in 2013 by Caesar Bita, an underwater archaeologist at the National Museums of Kenya, who recovered copper ingots and elephant tusks from the submerged site. Bita is now helping to coordinate the ongoing investigation, Castro said.

The wreck would be "archaeological stardust" if it proved to be the São Jorge, said Sean Kingsley, a maritime archaeologist and the editor of Wreckwatch magazine, who is not involved in the project.

"Kenya was a staging post for tapping into the dazzling wonders of the Indies," so any early European shipwrecks found there are "hot property," he told Live Science in an email.

However, further archaeological investigations will be necessary to determine whether this was one of da Gama's ships. "This is one wreck that screams out for protection, respect and care before its back story vanishes forever," Kingsley said.

Editor's note: This story was updated at 11:54 a.m. EST on Nov. 27 to note that if the wreck is confirmed to be part of Vasco da Gama's final voyage, the shipwreck may be one of the earliest, not the earliest, European shipwrecks in the Indian Ocean.

A shipwreck discovered during a search for dumped wartime ammunition in Norway's Lake Mjøsa has been identified as a local "føringsbåt" from up to 700 years ago. But bad weather has prevented researchers from finding out more.

The wreck, which lies at a depth of around 1,300 feet (400 meters), was found in 2022 by an autonomous underwater vehicle (AUV) mapping the lake for Norway's military.

The discovery caught the attention of researchers at the Norwegian University of Science and Technology (NTNU) based in the city of Trondheim. But they were not able to revisit the wreck until last month.

NTNU maritime archaeologist Øyvind Ødegård told Live Science that he and his colleagues explored the wreck for about an hour using a remotely operated underwater vehicle (ROV) tethered to a research boat on the surface. But technical issues and encroaching bad weather prevented the researchers from using the underwater drone to take wood samples for radiocarbon dating, so the wreck's exact age will remain unknown until they can return there next spring.

Several visible features of the wreck, however, indicate the vessel was built between 1300 and 1700, Ødegård said.

Related: 32 haunting shipwrecks from the ancient world

Norwegian lake

Lake Mjøsa is the largest lake in Norway and lies about 60 miles (100 kilometers) north of Oslo. It covers more than 140 square miles (360 square km), but only a few square miles of the lake bottom have been mapped. It was a vital trade route between the many prosperous communities along its shores from at least the eighth century.

Ødegård said the researchers now think the mysterious vessel was a "føringsbåt" used to carry cargo and passengers. Such boats were widely used on Norwegian lakes, but their flat-bottomed construction made them unsuitable for the open sea.

The latest explorations showed this particular føringsbåt was built with an upright stern, a feature introduced in Norway after about 1300; earlier Viking ships were the same on both ends. And there are signs that it may have had a central rudder at the stern for steering, whereas Viking ships used a specialized steering oar on one side, Ødegård said.

The boat was also built with wooden planks overlaid in a "clinker" style. This traditional Scandinavian boatbuilding method was superseded by the flush planks of the "carvel" style, an innovation from the Mediterranean.

Telltale planks

The 33-foot-long (10 m) wreck in Lake Mjøsa is covered with sediments, which Ødegård thinks may have been penetrated by the sonar equipment that located the wreck in 2022. The wooden planks in the hull that can be seen are relatively wide — a sign they were cut with an ax, rather than sawed at a shipyard.

"That is an indication that this wreck is older," Ødegård said.

The 2022 discovery was made with an AUV operated by the Norwegian military, but the latest explorations used an ROV operated by the university spin-off company Blueye.

The wreck now lies on the bottom of Lake Mjøsa in deep and calm waters, but the lake surface in that area has strong currents, Ødegård said.

In addition to preventing the researchers from reaching the wreck on several occasions, the currents may have caused the føringsbåt to founder.

"It's not the calmest spot," he said. "That leads us to guess that someone had an accident while crossing the lake."

Shipwreck hunters have discovered the wreck of a British submarine that sank near Greece in 1943, solving an 81-year-old mystery about its disappearance.

HMS Trooper, designated N91, went missing after a secret mission in early October 1943 to land three Greek resistance agents on Kalamos, an island on the west coast of Greece. The sub was then ordered to patrol in the Aegean Sea, where German forces were later known to have laid naval mines.

But the sub was reported missing and all 64 of its crew presumed dead when it failed to arrive in Beirut on Oct. 17, 1943.

Researchers led by Greek underwater expert Kostas Thoctarides have now located the Trooper's wreck, north of the central Aegean island of Donoussa in a region known as the Icarian Sea, which is plagued by bad weather.

"The Icarian Sea is one of the most difficult seas with strong winds, waves and strong underwater currents," Thoctarides told Live Science. "However, constant and persistent research paid off."

Related: 30 incredible sunken wrecks from WWI and WWII

Thoctarides is the founder and owner of the Greek underwater recovery company Planet Blue. He said 14 earlier expeditions had failed to locate the wreck of HMS Trooper because they were searching too far east, where the submarine had reportedly been seen on Oct. 14, 1943.

Icarian Sea

Thoctarides and other researchers studied wartime reports and determined that HMS Trooper may have sunk earlier in October 1943, among occupied Greek islands west of that area. Their research proved correct when they located the wreck of HMS Trooper on Oct. 3, 2024.

Thoctarides said the wreck was first found using shipboard sonar, which creates a detailed map of the seafloor using the reflection of sound pulses; and then explored with a "Super Achille" remotely-operated vehicle (ROV).

The Trooper now lies on the seafloor at a depth of about 830 feet (253 meters) — the eighth wartime submarine wreck that Planet Blue had discovered in Greek waters, he said.

A large explosion had broken the sub into three large parts — the bow, the midship, and the stern — which seems to confirm the researchers' suspicion that it sank after hitting a German naval mine.

It also indicates that the reported sighting of HMS Trooper on Oct. 14, 1943 was incorrect; instead, it seems the sighting was of another British submarine of the same class, Thoctarides said.

British submarine

According to a statement from Planet Blue, the badly damaged wreck has been identified by comparing it to the original shipbuilding plans.

An open hatch on the command or "conning" tower suggests the vessel was sailing on the surface when it struck the mine.

The wreck is a war grave, so it has not been disturbed in any way, the statement said; and the discovery may help bring closure to the families of those who died.

"I have been aware for many years of the strenuous effort by the Greek research team to locate the wreck of the submarine and am now very pleased and excited that their endeavours have been rewarded," Capt. Richard Wraith of Britain's Royal Navy and the son of the Trooper's commander, Lt. John Wraith, said in the statement.

"I hope that any family members of those lost with my father may be able to use the definitive location of Trooper as a focal point to help lay to rest any memories of their loved ones."

Editor's note: This article was updated at 2:13 p.m. EDT on Wednesday (Oct. 16) to correct the depth of the Trooper wreck, which is at about 830 feet (253 meters) under the water's surface.

Two years ago, sonar images revealed strange circles at the bottom of Lake Michigan that scientists couldn't explain. Now, a survey has determined the shapes are giant holes — but there are many more secrets left to unravel, researchers say.

The holes were first discovered in 2022, when researchers embarked on a mission to map the lakebed inside the Wisconsin Shipwreck Coast National Marine Sanctuary, a protected area of Lake Michigan that contains 36 known shipwrecks, and may contain many more. Weird circles appeared on the map that looked natural rather than human-made, Russ Green, a maritime archaeologist and superintendent of the sanctuary who took part in the mapping project, told Live Science in an email. The shapes were likely depressions in the lakebed, but the researchers couldn't be sure.

"Any kind of new discovery in the Great Lakes is exciting," Green said. "But these features really stand out — they are in deeper water (500 feet [150 meters] ish) and weren't known before, as far as we can tell."

Brendon Baillod, a local shipwreck hunter, spotted the mysterious circles around the same time as Green and his colleagues while searching for a sunken freighter. To his eyes, the circles were clearly depressions, or craters, measuring between 20 and 40 feet (6 to 12 m) deep, Baillod told Live Science in an email. "There were dozens of them in our search grid," he said. "Most were 500 to 1,000 feet [150 to 300 m] in diameter and of irregular shapes."

Related: Deepest blue hole in the world discovered, with hidden caves and tunnels believed to be inside

There was a lag in processing data from the initial mapping expedition, but Green, Baillod and their colleagues eventually contacted scientists at the National Oceanic and Atmospheric Administration's (NOAA) Great Lakes Environmental Research Laboratory (GLERL), Green said.

This year, the research teams conducted a joint survey to examine the circles more closely. On Aug. 21, they used a remotely operated vehicle to confirm that the shapes are enormous, naturally-occurring craters. Scientists counted roughly 40 of them, but there are likely more to be found, Steve Ruberg, a researcher at GLERL, told the Milwaukee Journal Sentinel.

The craters were like "perfect, little circles" on the lakebed about 14 miles (23 kilometers) southeast of Sheboygan, Wisconsin, Ruberg said, and extended southwards in a line toward Port Washington, also in Wisconsin.

Researchers previously found similar depressions at the bottom of Lake Huron, which borders Michigan and Canada. Those depressions turned out to be sinkholes, which are caverns that form — both underwater and on land — when groundwater dissolves the bedrock from below, causing the surface layer to collapse. Lake Michigan partly sits on limestone, which is prone to dissolution, so it's likely that the craters on the lakebed are also sinkholes, Ruberg said.

Others are holding off on calling the circles sinkholes until more research has been done. "I think they might be more accurately called craters, which have formed in the deep bottom sediment due either to water upwelling from below or trapped hydrocarbon offgassing," Baillod said.

The recent survey found no water escaping from the holes that would suggest there is groundwater circulating beneath the lakebed, but Ruberg said he expects researchers will eventually detect some. Images and videos of the holes showed freshwater shrimp, small fish and invasive quagga mussels "doing their thing in the dark down there," he said.

It's unclear what impact the holes might be having on Lake Michigan as a whole, but researchers are confident they will find out in time. "We'll be exploring them for years to come to learn more, and sort out how they got there and what role they play in Lake Michigan's ecosystem," Green said.

Shipwreck hunters in Scotland have located the wreck of a British warship that was sunk by a German U-boat in the North Sea nearly 110 years ago.

They said the wreckage is that of HMS Hawke, a 387-foot-long (118 meters) cruiser that quickly sank with 524 people on board after it was hit by a torpedo from the sub on Oct. 15, 1914.

Roughly 70 of the warship's crew survived by escaping into lifeboats, but the loss of life was still tremendous, Kevin Heath, a researcher with the Orkney-based Lost in Waters Deep group, told Live Science.

"This was very early — the beginning of the First World War," Heath said, adding that the British did not know at the time that U-boats had enough diesel fuel to reach Scotland. By the end of World War I, thanks to refueling in the mid-Atlantic, German U-boats had an even farther range and could reach the United States.

The Hawke was one of several British warships that had been assigned to blockade the German mainland — a tactic that kept most of the Imperial German Navy in port during the war. But the new submarine technology of the German U-boats allowed them to avoid the blockade and sink several Allied warships and civilian ships.

Related: 30 incredible sunken wrecks from WWI and WWII

U-boat threat

Heath said the Hawke was sunk by a torpedo from a U-boat designated U-9; it was commanded by Otto Weddigen, who would soon become famous in Germany. Just a few weeks earlier, Weddigen and U-9 had sunk three British cruisers patrolling the North Sea, causing more than 1,400 deaths.

According to historical accounts, the sinkings triggered an outcry among the British public and damaged the reputation of the Royal Navy. But these attacks also encouraged the British Admiralty to take the threat of German U-boats more seriously.

Heath said the wreck of the Hawke now lies on the seafloor beneath about 360 feet (110 m) of seawater and about 70 miles (112 kilometers) east of Fraserburgh, a coastal town in northeastern Scotland.

His group discovered it on Aug. 12 when they were returning from a dive to a seafloor obstruction that was marked on nautical charts but turned out to be nothing. The charted obstruction may have been an early estimate of the location of the Hawke wreck made with the less-accurate Decca navigation system used before the introduction of GPS, Heath said.

War grave

Heath and the Lost in Waters Deep group determined the rough location of the wreck thanks to reports of the sinking, including the logbook from the German U-boat.

The group has informed both the Royal Navy and the United Kingdom's Hydrographic Office, which produces electronic and paper nautical charts for the area, Heath said. The site of the Hawke wreck is a war grave and, therefore, can be protected by law from interference and possibly from all future attempts to dive there, he said.

At the moment, the only underwater images of the wreck were taken by the group's divers during their August expedition to the area. They show the wreck in "remarkable" condition, Heath told BBC News.

"Lots of the decking is still in place — teak decking," he said. Also, "there is a wonderful captain's walkway around the back of the stern [and] loads of guns, because obviously she was a warship."

Underwater archaeologists have located the wrecks of three military ships involved in Japan's invasion of Alaska's remote Aleutian Islands in World War II — an almost-overlooked conflict sometimes called the "forgotten battle" by historians.

The wrecks of the vessels — two Japanese freighters and the American cable ship SS Dellwood, which laid undersea cables during the war — were discovered last month during an expedition to Attu Island, at the westernmost tip of the Aleutians.

The Japanese ships were sunk by bombs from American aircraft after Japanese troops invaded the island in June 1942, roughly six months after the attack on Pearl Harbor, and the American ship sank about a month after the Japanese invasion had been defeated almost a year later, during efforts to reinforce the island's defenses.

"The original [Japanese] idea was to turn Attu into an 'unsinkable aircraft carrier'" for attacks on other American locations, maritime archaeologist and project co-leader Dominic Bush told Live Science.

"But as things started to change in the Pacific, they were abandoned by the Imperial command and basically told to hold out for as long as they could — essentially, to die with honor," added Bush, who was a doctoral student at East Carolina University (ECU) at the time of the expedition and is now a researcher for the archaeological nonprofit Ships of Discovery.

Related: 30 incredible sunken wrecks from WWI and WWII

Battle of Attu

Attu and the nearby Aleutian island of Kiska were the only parts of North America invaded and occupied by a foreign enemy during World War II, although Japanese warplanes also bombed other Aleutian islands. In response, the United States spent roughly a year bombing the Japanese there with warplanes and, eventually, drove out the Japanese with a force of almost 35,000 American and Canadian soldiers.

The final stages of the invasion included the Battle of Attu, which claimed the lives of 2,351 Japanese and 549 Allied troops in May 1943.

Bush and his colleagues at ECU — including the project's co-leader, maritime archaeologist and historian Jason Raupp — had spent years researching the Aleutian Island wrecks and were able to locate all three during a two-week expedition in July.

The researchers teamed up with several strategic partners, including the Japanese World Scan Project, which scans environmental and archaeological sites with drones and other robots, to find out as much as they could about the wrecks.

"Nobody had documented these wrecks before," Raupp told Live Science. "So we went out there and searched … and since we had about four years of research and preparation, it made the identifications easier when we found them."

Advanced sonar

The wreck hunters searched the area on board a former crab-fishing vessel — the Norseman II — which has been converted into a scientific research ship and is equipped with a remotely operated underwater vehicle that took video of the sunken ships. The wrecks were located by a sonar array towed behind the research ship; the array carried equipment for an advanced type of sonar called "synthetic aperture" sonar, which uses the reflections of sound pulses to locate objects underwater.

Raupp explained that the system combines new hardware and advanced software processing techniques to create three-dimensional scans of the seafloor over much greater distances and with much higher resolution than earlier sonar systems.

"It allows for increased efficiency of a survey, because you are able to cover massive swaths of the seabed with a high level of resolution," he said. "We would have needed weeks to achieve the same result using standard sonar."

The wreck of the Dellwood and one of the Japanese freighters, Kotohira Maru, were located offshore at a depth of about 300 feet (90 meters), and the wreck of the other Japanese freighter, Cheribon Maru, was found in shallow water near the shore.

Bush said the damage observed on the wrecks of the two Japanese freighters confirmed reports of their sinkings by bombs from American warplanes.

The sunken American ship had been laying cables for a new air base built there after the invasion when it struck an uncharted underwater pinnacle, Bush said, and the researchers had also found evidence that anti-submarine nets were used to defend Attu's main port from attacks by Japanese submarines.

Divers have retrieved more than 900 artifacts from two centuries-old shipwrecks hiding in the depths of the South China Sea.

In October 2022, researchers discovered the shipwrecks around 4,900 feet (1,500 meters) below the surface of the sea, which is bound by China to the north, Vietnam to the west and the Philippines to the east, according to a statement from the Chinese government.

The twin wrecks, which date to the Ming dynasty (1368 to 1644), sit less than a mile (1.5 kilometers) off the coast of Sanya, a city on China's Hainan Island. The sites are about 14 miles (22 km) apart, the South China Morning Post (SCMP) reported.

In 2023, researchers began the arduous task of mapping and excavating the sites using a deep-sea submersible called the "Shenhai Yongshi," or "Deep Sea Warrior," The Guardian reported.

"The wrecks are both relatively well-preserved and a large number of relics have been uncovered," Yan ­Yalin, director of the archaeology department for China's National Cultural Heritage Administration (NCHA), said at a news conference in 2023.

Related: 13 haunting shipwrecks from the ancient world

Now, researchers have used deep-sea-diving equipment to sift through the wreckage. They uncovered a wealth of porcelain and pottery pieces alongside copper coins at the first shipwreck site, according to the statement.

That vessel's cargo had originated from Jingdezhen, known as China's porcelain capital, the SCMP reported.

The second boat contained 38 artifacts, including lumber, porcelain and pottery items, spiral-shaped turban shells and deer antlers, according to the statement.

Both wrecks highlight the importance of "trade and cultural exchanges along the ancient Maritime Silk Road," Guan Qiang, deputy head of the NCHA, said in the statement. 

No details were given about the cause of the shipwrecks. 

Shipwrecks can reveal fascinating details about the ancient world. They can tell us what goods people were trading, how ships were being built and can even provide information on the rituals that people were carrying out. 

In this countdown, Live Science takes a look at 32 shipwrecks from the ancient world. Some are small watercraft, like canoes, while others are large, seagoing ships. 

Marsala Punic shipwreck

Discovered by a dredge ship near the city of Marsala, off the western coast of Sicily, the Marsala Punic shipwreck dates back around 2,300 years. The ship was built by the Carthaginians, a people based in the city of Carthage in what is now Tunisia. They fought a series of wars against the Roman republic, and eventually, Carthage was destroyed by the Romans. The ship was about 115 feet (35 meters) long and was well-preserved. Only a small number of artifacts, including a spearhead, an anchor and ballast stones, were found with the wreck. 

Rhine Roman troop transporter

The Roman Empire controlled a vast area that stretched from northern England to Syria. Its most important frontier stretched across central Europe, including parts of Germany. Over the years, a number of small ships used for troop transport have been discovered in the region. The example seen here dates to the fourth century A.D. and is made of oak. This vessel, and other transports that have been found, are on display at the Museum of Ancient Seafaring in Mainz, Germany. 

Nemi ships

Located in Lake Nemi, the Nemi ships consist of two vessels that were built on orders of the Roman emperor Caligula (reign circa A.D. 37 to 41) John McManamon, professor emeritus of archaeology at Loyola University Chicago, wrote in his book "From Caligula to the Nazis: The Nemi Ships in Diana's Sanctuary" (Texas A & M University Press, 2023). Why the massive ships were created is a mystery, noted McManamon. There is a temple to Diana, goddess of wild animals, on the lake but whether that has anything to do with the vessels is uncertain. The remains of the ships were destroyed during World War II. 

Peristera shipwreck

The Peristera shipwreck dates back around 2,400 years and is located near Peristera island in the Aegean Sea. It contains about 4,000 amphorae weighing between 62 pounds (28 kilograms) and 82 pounds (37 kg) each, researcher Fredrik Søreide wrote in his book "Ships from the Depths: Deepwater Archaeology" (Texas A&M University Press, 2011). It's located at a depth of about 66 feet (20 m) beneath the sea. With its immense cargo, the wreck demonstrates the sheer weight of goods that ships of the time were capable of carrying. 

Pesse Canoe

The Pesse Canoe was discovered in 1955 near the village of Pesse, in the Netherlands, during the construction of a motorway. Dating back about 10,000 years, it is the oldest surviving boat in the world, according to the Drents Museum. It is 10 feet (3 m) long and 17 inches (44 centimeters) wide and was dug out with an ax from a pine log, the museum notes. To prove that it was used as a boat, a replica was created and a person successfully paddled in it. 

Dokos shipwreck

Discovered in 1975 near the island of Dokos in the Aegean Sea, the Dokos shipwreck contains a variety of pottery dating back around 4,500 years. The ceramics found include cups, jars, amphoras, jugs and bowls, archaeologist Shelley Wachsmann wrote in his book "Seagoing Ships and Seamanship in the Bronze Age Levant" (Texas A&M University Press, 1998). No timber remains of the ship have been found, possibly because the ship has completely degraded away. 

Antikythera 

The Antikythera shipwreck, named after the island of Antikythera in the Aegean Sea, dates back about 2,000 years. Found in 1901, it contains a variety of artifacts, the most famous being the Antikythera mechanism, a shoebox-shaped device that is sometimes called the world's oldest computer. The device could determine the motion of the sun, moon and five of the planets and could even tell when athletic competitions, such as the Olympics, were set to take place. The remains of statues, including at least one depiction of Hercules, have also been discovered in the shipwreck. 

Sea of Galilee boat

In 1986, the remains of a boat that dates back around 2,000 years, around the time of Jesus, was discovered on the northwest coast of the Sea of Galilee, according to the Yigal Allon Centre. It's been radiocarbon dated between 100 B.C. and A.D. 100. The boat underwent conservation and is now displayed at the center. The gospels state that Jesus and his disciples used boats to travel the Sea of Galilee, and this vessel gives an idea of what they may have looked like. 

3,000-year-old Native American canoe

In 2022 a 3,000-year-old dugout canoe was discovered in Lake Mendota in Madison, Wisconsin. It's about 14.5 feet (4.4 m) long and was carved from a single piece of a white oak tree, the Wisconsin Historical Society said in a statement. It was found just one year after a 1,200-year-old canoe was discovered in the same lake, the historical society noted. It's possible that there is a now-submerged Native American village near where the canoes were found. 

Chiessi shipwreck 

Dating back around 2,000 years, the Chiessi shipwreck was found off the coast of Chiessi, a village on the west coast of the island of Elba in Italy. The ship contained 5,000 to 7,000 amphorae — two-handled jars — which appear to have been manufactured in Spain, wrote Candace Rice, an assistant professor of archaeology and classics at Brown University in a paper published 2016 in the Journal of Roman Archaeology. Much of the cargo consisted of products made from salted fish, wrote Rice, with a small number of amphorae carrying olive oil. 

Lead ingots shipwreck

About 2,000 years ago, a Roman ship carrying a cargo that included massive lead ingots sank in the Mediterranean. The heaviest ingot weighs 150 lbs (68 kg), a number equal to about 205 Roman pounds, per the University of Alicante. Markings indicate that the largest ingot belonged to the Roman emperor, possibly Nero. Additionally, about 3,000 jars of fish sauce were loaded onto the vessel. The vessel was about 105 feet (32 m) long and was likely traveling from Cadiz to Rome at the time it sank. 

Mahdia shipwreck

A ship went down off the coast of Tunisia around 2,100 years ago and was discovered by fishermen from the village of Mahdia in 1907, according to the National Gallery of Art. It contained a variety of artifacts, including bronze and marble sculptures, 22 bronze beds, at least 60 marble columns and a highly-decorated candelabra, the museum notes. One particularly interesting artifact is a stela (a stone with a carving engraved on it) depicting Dionysus, a Greek god associated with wine-making and revelry. 

Ses Fontanelles

The Ses Fontanelles ship sank around 1,700 years ago near the Spanish island of Mallorca in the Mediterranean. It was carrying about 300 sealed jars, many filled with fish sauce made from anchovies. Some of the jars contained oil from plants and may have held wine, olive oil or olives mixed with vinegar. Some of the jars have a Christian monogram on them, suggesting that they were being sold by a Christian church authority. The wreck dates to around the time of Constantine, a Roman emperor who legalized Christianity and eventually converted to it. 

Uluburun shipwreck

The Uluburun shipwreck was found in 1982 by Turkish sponge divers near the town of Kaş, off the southern coast of Turkey. Dating back around 3,300 years, it contains a large amount of copper and tin ingots. The ratio of copper to tin in the shipwreck was 10:1, which is close to the ratio needed to make bronze. Other goods include carved ivory containers, gold jewelry and semi-precious stones, such as carnelian and agate, per the Institute of Nautical Archaeology. Weapons and musical instruments, such as lutes, were also discovered. 

Kyrenia shipwreck

Discovered in 1965 off the northern coast of Cyprus, near the town of Kyrenia, the Kyrenia shipwreck dates back around 2,300 years. The ship carried a cargo of up to 500 amphoras and 27 stones that were used as ballast, the Institute of Nautical Archaeology notes. A reconstruction of the hull suggests that the ship was about 46 feet (14 m) in length. Fragments of lead were also found, and it appears that the ship's hull was covered with lead to protect it against marine life, the institute notes. 

Bajo de la Campana Phoenician shipwreck

This ship sank around 2,700 years ago near Bajo de la Campana off the southeastern coast of Spain. The ship was used by the Phoenicians, a people who flourished in the Mediterranean from roughly 1500 to 300 B.C. The ship's cargo included 10 elephant tusks, 28 small tin ingots and two copper ingots, per the Institute of Nautical Archaeology. Galena (lead ore) nuggets, pine cones and even wooden combs were found in the remains of the wreck. 

Mazarron 2 shipwreck

Found in 1995 off the southeast coast of Spain, near the town of Mazarron, the Mazarron 2 shipwreck dates back around 2,700 years. The ship's cargo includes lead ingots, an amphora and a hand grinder, according to Spain's Ministry of Culture. An anchor made of lead and wood was discovered and is one of the earliest known examples of a constructed anchor, the ministry said. 

Ma'agan Michael ship

The Ma'agan Michael ship was found near Kibbutz Ma'agan Michael in Israel. Dating back around 2,400 years, its cargo includes a set of wooden carpenter tools, 12 tons of rocks and ceramic vessels, per the Hecht Museum. The ship is about 44 feet (13 m) in length and 13 feet (4 m) in width and is well-preserved, according to the museum. It appears that the ship was beached for some reason, and the crew didn't return to it. 

Hjortspring boat 

Dating back around 2,300 years, the Hjortspring boat was found in the bog of Hjortspring Mose in Denmark and is northern Europe's oldest plank vessel, according to the National Museum of Denmark. The boat is almost 66 feet (20 m), weighs 1,168 lbs (530 kg) and could carry 24 people with weapons and equipment, the museum notes. The boat's planks are made of lime wood,it has oars made of maple and it has curving extensions at each end. 

Kumluca shipwreck

Dating back around 3,500 years, the Kumluca shipwreck is located near the town of Kumluca, off the southern coast of Turkey. Research conducted in 2019 and 2022 found that the shipwreck contains about 100 metal ingots, many of which are encrusted together on the bottom of the sea, per the Institute of Nautical Archaeology. Two disk-shaped balance weights made of lead were also found, along with ceramic fragments and small stones used as ballast, the institute notes. 

Roman shipwreck off Caesarea

Dating back around 1,700 years, a Roman ship found off the coast of Caesarea in Israel contains a vast number of artifacts. These include hundreds of Roman coins made of silver and bronze as well as Roman statues and figurines, according to the Armstrong Institute of Biblical Archaeology. The shipwreck was found at a depth of just 13 feet (4 m) and may have wrecked during a storm, the institute notes. Another medieval shipwreck dating back around 600 years is located nearby. 

Tang shipwreck

The Tang shipwreck (also known as the Belitung shipwreck) is a ninth century A.D. Arab dhow that sank near Belitung island in Indonesia, per the UNESCO Silk Roads Programme. It was found by local fishermen in 1998 and is one of the oldest shipwrecks in the region. The shipwreck contains 60,000 artifacts that date to China's Tang dynasty (A.D. 618 to 907). Most of the artifacts consist of a specific type of ceramic known as "Changsha ware."

Nanhai No. 1 shipwreck

The Nanhai No. 1 shipwreck, as it is now called, is about 98 feet (30 m) long and 33 feet (10 m) wide, per the UNESCO Silk Roads Programme. It may have been built during the Southern Song dynasty ( A.D. 1127 to 1279). About 60,000 artifacts were found inside, including porcelain vessels, iron wares, copper coins and copper rings, UNESCO notes. It was found about 82 feet (25 m) beneath the surface in 1987 but was not excavated until 2007. 

Quanzhou ship

Discovered in 1973, the Quanzhou ship (also called the Quanzhou wreck) dates to the Song Dynasty (circa A.D. 960 to 1279), possibly to its final years before the dynasty was taken over by the Mongols. It was found near the city of Quanzhou in the Taiwan Strait. More than 500 coins, the latest dating to the 13th century A.D., were found inside it. The remains of spices, such as pepper, were also found in its remains. 

Godawaya shipwreck

Found by fishermen in 2003 near the settlement of Godawaya (also spelled Godavaya), off the south coast of Sri Lanka, the Godawaya shipwreck dates back around 2,100 years. Located about 108 feet (33 m) beneath the sea, it might be the remains of a Roman ship, per the Institute of Nautical Archaeology. The remains include iron ingots, ceramic bowls and glass. It is likely the oldest known shipwreck in the Indian Ocean. 

Nydam boat

Discovered in a bog at the site of Nydam Mose near the eastern coast of Denmark, the Nydam boat was discovered in 1863 and dates back around 1,600 years. It's one of the oldest clinker-built boats in northern Europe. Clinker building involves having planks of the boat overlapping each other to help reinforce and strengthen the hull. The boat may not have been accidently lost but rather may have been intentionally sunk in the bog as part of a ritual. 

Khufu ship

While calling this a "shipwreck" is a bit of a stretch, the Khufu ship is one of the most famous surviving ships from the ancient world. It was buried beside the Great Pyramid, which was constructed on orders of the pharaoh Khufu (reign circa 2551 to 2528 B.C.). The boat is 141 feet (43 m) long and was dismantled before being placed in a pit beside the Great Pyramid, according to the Institute of Nautical Archaeology. The ship's builders used a mortise and tenon system to fasten the planks, the institute notes. 

Arles Rhône 3

Discovered near the Rhone River in France in 2004, the "Arles Rhône 3" ship, as it is now called, is a barge that dates back around 2,000 years. It is 102 feet (31 m) long and about 10 feet (3 m) wide, according to the French Ministry of Culture. The barge was intended for inland navigation on rivers and was carrying a cargo of limestone blocks when it sank. After it sank, it was kept well-preserved by a layer of mud that rapidly accumulated over it, the ministry said. 

Zwammerdam ships

The Zwammerdam ships (also known as the Zwammerdam boats) consist of three Roman canoes and three Roman barges. They were discovered near the village of Zwammerdam in the Netherlands in the 1970s, per Leiden University. The six vessels date between A.D. 80 and 200, a time when the Netherlands was on the northern frontier of the Roman Empire. The vessels were well-preserved when they were discovered but had to be taken apart in order to be removed. In 2016, a project began that aims to put the vessels back together. 

Dover Bronze Age Boat

Dating back around 3,500 years, the Dover Bronze Age Boat was discovered in 1992 by construction workers building a road link. The boat is the "world's oldest known seagoing boat," the Dover Museum states. During excavations, archaeologists had to cut the surviving pieces of the boat up in order to remove it and were able to recover 31.2 feet (9.5 m) of the boat. It's uncertain how large the boat was originally, but it was probably longer than 31 feet, the museum notes. 

Brigg logboat

Discovered in 1886 by workers building a gasometer (also known as a gasholder) near the town of Brigg on the River Ancholme in Lincolnshire, England, the Brigg logboat dates back around 2,900 years. It is 48.6 feet (14.8 m) long and 4.6 feet (1.4 m) wide and was carved from a single oak log, per the Hull Museums Collection. A small wooden shelf was found near the bow of the boat and may have been used by the person in charge of steering the vessel. Much of the boat was destroyed during an air raid in June 1943. 

Gozo shipwreck

Discovered in 2007 during an offshore remote sensing survey, the Gozo shipwreck is located near the island of Gozo in Malta. It's a Phoenician shipwreck dating back to the seventh century B.C., per the Phoenician Shipwreck Project. The artifacts found inside include stone querns, used to grind food, and urns that were intended to hold the cremated remains of the dead. The discovery of the urns was surprising, as Phoenician urns are usually found within burial grounds or other funerary contexts, and it's unusual to find examples in a shipwreck. 

Shipwreck hunters have discovered the remains of a famous American submarine that sank with 79 crew on board while fighting a Japanese warship near the Philippines in 1944.

According to the New York-based Lost 52 Project, which made the discovery, the wreck of USS Harder now lies on its keel on the bottom of the South China Sea near the northern Philippine island of Luzon at a depth of around 3,750 feet (1,140 meters).

Naval reports of the sub's final mission say the Harder — a Gato-class sub named after a type of fish (the harder mullet) and nicknamed the "Hit 'Em Harder" — sank with all crew on Aug. 24, 1944 after it was heavily damaged by depth charges in a battle with a Japanese destroyer.

The Harder was one of the most famous American submarines of World War II. U.S. Navy records report that it torpedoed and sank five Japanese destroyers and several other enemy ships during six successful patrols in the Pacific war theater.

"This is one of the most celebrated WWII submarines and an historic naval discovery," Tim Taylor, the founder of the Lost 52 Project, told Live Science in an email.

Related: 30 incredible sunken wrecks from WWI and WWII

War grave

Taylor is the CEO of a company called Tiburon Subsea, which uses autonomous underwater vehicles (AUVs) and other technologies to collect data at underwater sites. He also leads the Lost 52 Project, which aims to locate the wrecks of the 52 American submarines lost at sea during World War II and four lost during the Cold War. 

The group has already located the wrecks of eight vessels, making the wreck of USS Harder their ninth discovery, Taylor said. Each of the underwater wrecks is also a war grave for the crewmembers who died when it sank, and the missing crew of the Harder were remembered for their service when the wreck was found.

"We have a protocol that, when we locate a submarine, we memorialize the crew," Taylor said. "We observe a minute of silence, ring the bell for every member of the crew and have a prayer service led by a deacon who is part of our expedition team."

The team located the wreck by studying reports of its final battle and then searching suitable areas with shipboard sonar, which can reveal objects on the seafloor, and AUVs, which can go much deeper than human divers.

But even after they take steps to make the search patterns as efficient as possible, "It is a long and arduous process, like looking for a needle in a haystack," Taylor said.

Sunken sub

The extreme depth of the wreck meant that AUV searches were essential, although a period of relatively good weather in recent weeks made the search easier. 

The Harder wreck is too deep to be visited by divers, and the U.S. Navy has designated the wreck as a protected site. "The wreck represents the final resting place of sailors that gave their life in defense of the nation and should be respected by all parties as a war grave," the Navy said in a statement.

Taylor added that the AUV images show that the vessel appears to be in good condition. "The submarine is relatively intact, minus the damage done by the depth charges," he said. 

And now, after 80 years under the waves, the wreck seems to be a thriving home for sea life, including an octopus that Taylor saw in the AUV images. 

"It is a protected gravesite for 79 US WWII sailors, but there is a lot of life on the submarine," he said. "It's quite extraordinary."

A Roman-era shipwreck on the Spanish Mediterranean island of Mallorca was carrying a cargo of highly prized fish sauce when it sank around 1,700 years ago, a new study finds.

The Ses Fontanelles wreck lies in shallow water a few hundred feet from the beach near Les Meravelles, a resort town about 4 miles (6 kilometers) southeast of Palma, the capital of Mallorca (also spelled Majorca), where it was discovered after a storm in 2019.

Previous archaeological studies suggest the ship originated from or near the Spanish port of Cartagena — known as "Carthago Spartania" to the Romans — but sank because of unknown circumstances in the fourth century. 

The latest study, published March 21 in the journal Archaeological and Anthropological Sciences, reports the most detailed analysis of the wreck yet. It reveals that many of the 300 sealed pottery jugs, or amphorae, in the ship's cargo contained fish sauce made from anchovies — a delicacy known in Latin as "liquamen."

It's unusual to find such a well-preserved wreck from this period, said study lead author Miguel Ángel Cau Ontiveros, director of the University of Barcelona's Institute of Archaeology and a research professor for ICREA, the Catalan Institution for Research and Advanced Studies.

"It is the only Late Roman shipwreck we know of so far from the area of Carthago Spartania [and] one of a few from the fourth century in the Mediterranean," he told Live Science.

Related: 'There's a great hidden museum in the Mediterranean': Underwater archaeologist David Gibbins takes us on a journey to 12 shipwrecks around the world

Roman wreck

Because the wreck lies in shallow water — an average of roughly 8 feet (2.4 m) below the surface — it was difficult to investigate amid the waves crashing near the shore. "It makes things very complicated when the sea is slightly moving," Cau said. 

He thinks the remarkable preservation of the wreck and its many organic items — which would usually rot away quickly — was probably because the ship was immediately buried by sand and other sediments after it sank.

In addition to the amphorae, archaeologists found ropes, shoes, a wooden drill and organic "dunnage" or matting, made from vine shoots and grass, that was used to protect the ship's hull from the cargo, Cau said.

Many of the amphorae still contain residues of the substances they held; and the latest study used gas chromatography and other analytical methods to create a snapshot of Mediterranean trade in the fourth century, he said.

Many of the amphorae contained the remnants of fish sauce, while others held oil from plants — likely olives, wine, and perhaps olives preserved in vinegar. The distinctive amphorae for different products were labeled with painted inscriptions known as "tituli picti" in Latin, he said.

"The presence of so many painted inscriptions on the amphorae make us think that this was a common practice," Cau said.

Precious cargo

Previous studies found that many of the oil amphorae had seals stamped with a "Chrismon," or Christian monogram — similar to the Chi-Rho symbol of Constantine — which suggested they may have been marketed by a church authority, Cau said.   

In another key discovery, the wooden "step" connecting the mast to the hull was found to contain a coin from Roman Siscia (in modern-day Croatia), in line with Roman rituals for blessing a ship. The coin was made during the reign of the Roman emperor Constantine the Great and fixed the earliest possible date of the ship as A.D. 320.

"This matches well with all the archaeological study of the materials recovered in the excavation that suggest that the boat sank around the mid-fourth century," Cau said.

The ancient Romans were big fans of fish sauce and enjoyed several different types. The most famous may be "garum," which seems to have been a luxury product made from fermented fish viscera (guts) and blood, but "liquamen" seems to have been made from whole fish.

The archaeological analysis found fragments of fish bones in some of the amphorae from the Ses Fontanelles wreck, which indicated the "liquaminis flos" they were labelled as holding — Latin for liquamen "flower," which may have meant "best liquamen" — was made mostly from anchovies but contained some sardines.

Underwater archaeologists in Sweden have determined that a chest in the wreck of a 15th-century warship held tools to make lead shots for early handguns. The finding hints at key changes in naval battles at the time.

The chest is in the wreck of the Gribshunden ("Griffin hound"), a Danish royal "floating castle" that sank in 1495 at an anchorage in southern Sweden after a fire attributed to the mishandling of gunpowder.

The discovery could shed new light on the fate of the vessel, according to Rolf Warming, a maritime archaeologist and doctoral student at Stockholm University. Warming co-authored a new report on the weapons chest and other new finds from the Gribshunden wreck with Johan Rönnby, a maritime archaeologist and professor at Södertörn University in Sweden. The wreck was discovered by recreational divers in the 1970s, and Rönnby has studied it since 2013.

The discovery also hints at an early development in naval warfare from ramming and engaging in hand-to-hand combat — the tactics used since ancient times — to attacking enemy ships at a distance with gunfire, Warming said. But he stressed that it took more than a century for the development to become widespread.

"This is very much at the beginning of what we call the 'military revolution at sea,'" Warming told Live Science. "The tactics and technology for that were only fulfilled in the second half of the 17th century."

Related: 30 incredible sunken wrecks from WWI and WWII

Weapons chest

Warming and Rönnby used photogrammetry, a technique that involves digitally stitching together photos, to create a precise, virtual 3D model of the weapons chest. The chest is still underwater at the wreck site in coastal islands near the Swedish town of Ronneby, but Warming hopes it will be recovered soon. Conserving its contents will be a lengthy process, he said.

Based on what can be seen in the top layer of the chest, it contained several differently sized molds for the ball-shaped lead shots used in early handguns, plates of lead to be melted down for the molds, and cylinders that appear to have been canisters for gunpowder.

The researchers identified the chest as a "zeuglade," a type of tool chest that was used to make ammunition and which contemporary illustrations show on battlefields of the time.

They think the chest belonged to a company of German-speaking mercenaries on the ship when it sank; and a shirt of chain-mail armor, made of brass in the Bavarian city of Nuremberg in the early 1400s, was found elsewhere on the wreck, Warming said.

The cylinders in the zeuglade are similar to those known to have stored gunpowder, he said. But it wasn't clear if any powder they held was also used in the ship's many swivel guns, nor whether their mishandling led to the fire and explosion on the vessel — a possibility that was later suggested.

Diplomatic mission

The Gribshunden was the flagship of the Danish king Hans (or John), who was going to the Swedish town of Kalmar when the vessel sank. Hans and his retinue were not on board at the time.

Kalmar had been the site of a 14th-century agreement to unite Denmark, Norway and Sweden under a single monarch, known as the Kalmar Union. But it had fallen into abeyance, and in 1495, Hans had been trying to persuade Sweden to rejoin the union, with Hans as its ruler.

Learning more about the fire that sank the Gribshunden might help resolve lingering questions about it, Warming said. He noted that the ship's diplomatic mission meant there were probably fewer soldiers on board than its full complement in times of war.

Warming and Rönnby also found evidence of "elevated combat platforms" built above the bow and stern of the Gribshunden. The soldiers would have used these platforms during naval battles, perhaps to bombard their enemies with crossbows and firearms.

Such platforms were the origin of the shipboard term "fo'csle," meaning "forecastle," Warming said; and the Gribshunden one of the earliest ships where these platforms had been built into the hull, rather than being added after the ship's construction.

Editor's note: Updated at 9:40 a.m. EDT on April 24 to note that Danish king Hans was going to the town of Kalmar when the vessel sank, not returning from it as was previously stated. Also, that the Gribshunden was one of the earliest ships with a forecastle, not the earliest. 

In his lifelong career as an underwater archaeologist, David Gibbins has explored dozens of shipwrecks around the world. Now, in his new book, "A History of the World in Twelve Shipwrecks" (St. Martin's Press, 2024), Gibbins takes readers along for the journey as he visits sites from the ancient Egyptians, the Vikings and beyond. Live Science talked with Gibbins about his experience as a diver and the ways ships were the force connecting the spread of people, religion and ideas around the world. 

(This interview has been edited lightly for length and clarity.)

Jennifer Nalewicki: What initially sparked your interest in diving and eventually led you to write this book?

David Gibbins: As a small boy in the 1960s, I developed a fascination with diving. This was during a time of great adventure, when diving was as much a part of the great frontier due to people like Jacques Cousteau as space travel was. I was at that critical age when you tend to develop lifelong enthusiasms, so professionally, I became an archaeologist specializing in maritime archaeology. 

I spent time teaching as an academic before becoming a full-time writer. I began developing an idea for a book that was scholarly but also accessible. The fact that my own experiences have taken me from the Bronze Age all the way to the 20th century in terms of sites that I've dived has allowed me to pick and choose which shipwrecks to include. This book is a bit autobiographical and is a fantastic way to delve into these sites and use them as a springboard to write an idiosyncratic history of the world.

JN: How is exploring shipwrecks different from investigating land-based archaeological sites?

DG: The overwhelming difference is that while diving, you're limited [by] the amount of time you can spend at a site. Even at shallow shipwrecks, you only have enough air supply to explore for about an hour and a half. That means that the kind of reflection you can engage in at a typical land dig site, where you're spending days wandering and looking at it, you can't really do underwater. The whole experience of working underwater is very much intensified by the physical constraints of diving. 

There's also the environment, where you're doing something unfamiliar by going underwater. We think of diving as something that's accessible and done by a lot of people. But it still has that edge to it, since you must be aware of your limitations. How you excavate underwater is also different. I would say that underwater is often better because you can excavate with huge finesse using air lifts and dredging to take away the spoil and reveal things that are often better preserved underwater than they would be on land. 

Related: Diver unexpectedly discovers Roman-era shipwreck carrying beautiful marble columns off Israel's coast

JN: In your book, you say that shipwrecks reveal a single moment in time. What do you mean by this?

DG: A typical wreck represents one extraordinary moment in time, which is an emotionally powerful thing, since you're not far from thinking of the people on the ship — and, very often, sadly, what happened to them. At land sites, you often see an accumulation of debris and discard over the course of many centuries, and the exactitude of the data collected from the site can be constrained because you're simply unable to associate the artifacts with each other unless they're stratigraphically defined. Whereas at a wreck, you can be confident that everything there was in use at the moment of destruction.

JN: You also wrote that shipwrecks provide access to individuals. How is that?

DG: One example is the wreck of the Mary Rose, [Henry VIII's warship] that sank off the coast of England in 1545. It went down so quickly that everything was preserved inside, including the physical remains of many of the people onboard. This is because the ship had anti-boarding rope strung over the top deck, trapping people as they tried to escape. The osteo-archaeological studies that have been conducted since the wreck was raised in 1992 have revealed so much about these individuals, who were largely nameless, including identifying their place of origin and diets. Even though they're anonymous, they paint an extraordinarily detailed picture of individuals at the time.

JN: In what ways did seafaring impact the spread of religion, cultures and ideas across the globe?

DG: Even in societies as early as the Bronze Age, we often think that people were isolated, but there was communication and transportation happening between different regions at that time. For example, I discuss a very basic vessel from the Bronze Age found in southern England. It showed that people had the capacity to travel quite considerable distances across the English Channel. 

Another ship I mention is from the ninth century from the island of Belitung, Indonesia. This ship is fascinating because it shows the interconnections between classical antiquity and the rise of the medieval world and reflects that there was transport happening between places in the early-Islamic world [in what we now know as] Iran, Iraq, Arabia, Indonesia and China. This can be seen in the ship's cargo, which includes Chinese pottery coming west. I think wrecks are crucial to our understanding of the nature and extent of cultural communications over long distances. 

JN: One shipwreck you included is a merchant ship that sailed during King Tut's reign. What do its contents tell us about the ancient Egyptians?

DG: There are a few very interesting artifacts, one of which is a gold scarab of [Queen] Nefertiti. Whether or not she had direct involvement with this vessel is unclear, but it's thought that pieces of gold that made their way from Egypt were being transported west to Mycenae, Greece. Enough Egyptian artifacts have been found to show that Bronze Age Greeks were engaged in diplomatic, social and economic interactions with Egypt.

JN: Are there any other shipwrecks out there that you hope to explore one day? 

DG: In the last 60, 70 and 80 years of exploration in waters that scuba divers can reach, which is about 150 to 200 feet [45 to 60 meters] deep, many shipwrecks have already been found. What is still open for exploration is the huge expanse of much deeper waters. The Mediterranean is a very deep sea, and only the edges of it are accessible to divers. It's only been recently that exploration has begun on an intensive scale of wrecks in deeper waters. 

One of the golden prizes of Mediterranean archaeology would be ships carrying works of art from Greece to Rome at the time that Rome conquered Greece in the second century B.C. A considerable proportion of those ships didn't make it, and I think there's a great hidden museum in the Mediterranean containing bronzes and other works of art just waiting to be found. 

Archaeologists in the Bahamas have identified the underwater wrecks of 14 sailing ships involved in the trans-Atlantic slave trade between Africa and the Americas, a new report finds.

The wrecks include the Peter Mowell, an American schooner that sank off Lynyard Cay near Great Abaco Island in 1860 with about 400 enslaved Africans on board; as well as smaller vessels that carried slaves to plantations for sugar, coffee, cotton and tobacco in North America and around the Caribbean.

Most of the wreck sites have been identified only from 18th- and 19th-century records and remain unexplored, but the locations of some of them have already been found.

Related: Enslaved people were kidnapped from all across Africa, rare look at DNA from colonial cemetery reveals

The team has physically located three of the wrecks, but "for now, they are all under wraps," Carl Allen, CEO and founder of the underwater archaeological group Allen Exploration, told Live Science in an email. "These wrecks are not only historically important for investigating what life was like on slaver ships, [which is] poorly understood archaeologically, but they are physical witnesses to the knowledge base behind this horrific trade."

Fatal trade

The slave ships were identified during Allen Exploration's Bahamas Lost Ships Project, which is compiling an inventory of every shipwreck around the islands. So far, the team has identified 596 wrecks in the waters around the northern Abaco islands, and the oldest is from 1657.

The group is working on the project with the Bahamas Maritime Museum in Freeport on Grand Bahama, which published the report on the slave ships in its Ocean Dispatches series to coincide with Black History Month.

Michael Pateman, director of the Bahamas Maritime Museum and co-author of the report, told Live Science that the history of the Bahamas was profoundly influenced by several slaving events. They include the arrival of the first slaving vessels from Africa in 1721, which defined the population of the islands; more than 90% of the people who live there today are of African descent. 

The Bahamas were also the scene of the 1841 revolt on the slave ship Creole, which was transporting slaves from Norfolk, Virginia, to New Orleans. But some of the 135 enslaved people on board the ship seized it and forced it to sail to the Bahamas instead, where they claimed their freedom — a major milestone in the history of the trans-Atlantic slave trade, Pateman said.

The wrecks' locations show that the Bahamas served as a major crossroads between Africa, the American Southeast, Cuba and the Gulf of Mexico.

The region is known for its bad weather, but "it was the safest route," James Jenney, director of research for the Bahamas Lost Ships Project and co-author of the report, told Live Science in an email.

Island route

For many of the wrecks in the northern Bahamas, the ships sank when they were heading south from American ports toward the Northeast Providence Channel between Grand Bahama and Andros Island. "If you wanted to get to Havana and Cuba's sprawling plantations, you had to risk these waters," Jenney said.

The sugar plantations in Cuba were an especially dire destination for enslaved Africans.

"Conditions varied, but the fact that Havana was known as the 'banqueting place of death' says it all," underwater archaeologist Sean Kingsley, director of Wreckwatch International and co-author of the report, told Live Science.

He noted that enslaved African workers lived in miserable huts said to be "unfit for the habitation of wild beasts"; they wore iron slave collars and worked seven days a week, with just four hours a day of rest in cane-cutting season. About 10% of enslaved Africans died on the plantations in Cuba each year during the slave trade, and some were flogged to death, he said.

The next steps include diving to some of the wrecks to see what's left, in some cases after more than 200 years since the ships sank.

Report co-author James Sinclair, director of archaeology for Allen Exploration, said many were in shallow, warm waters and "high energy zones" — that is, with a lot of waves and storms — that have negatively impacted the sites.

"Our goal is to record what's left and figure out how to better preserve rare remains," he told Live Science.

Editor's note: Updated at 9:06 p.m. EST on March 4 to include an illustration of a ship carrying enslaved Africans. 

The first ever full-scale digital scan of the Titanic has revealed the world's most famous shipwreck in "astonishing," never-before-seen detail.

Caked in mud and surrounded by pitch-black water, the corroded wreck of the Titanic was scanned by submersibles using deep-sea mapping to create "an exact 'digital twin'" that experts will use to shed light on the ship's final hours above water.

After being struck by an iceberg just four days into its maiden voyage from Southampton, England to New York City in April 1912, the ship plunged to its current resting place 12,500 feet (3,800 meters) below the surface in the North Atlantic, roughly 370 nautical miles (690 kilometers) south of Newfoundland, Canada. Of the ship's 2,240 passengers and crew, more than 1,500 people died following the catastrophic crash.

The sunken ship's remains were unexpectedly discovered during a secret Cold War mission in 1985. Since then, divers have explored the wreck a number of times, photographing artifacts left behind in the chaos of the ship's sinking. Now the new scan — showing the full ship unobscured by gloomy water — may help scientists better understand how it veered into the iceberg and how it sank.

Related: An aurora that lit up the sky over the Titanic might explain why it sank

"This model will allow people to zoom out and to look at the entire thing for the first time. So, by capturing this 3D model, what we're able to do is visualize the wreck in a completely new way, there's all kinds of amazing small little details that you can see," Gerhard Seiffert, a 3D imaging specialist at the deep-sea mapping company Magellan that conducted the scan alongside the filmmakers Atlantic Productions, said in a statement. 

"This is the Titanic as no one had ever seen it before," Seiffert said.

Researchers created the unprecedented scan by stitching together more than 715,000 sonar images of the wreck with 4K video footage, taken during more than 200 hours of surveying with two submersibles named "Romeo" and "Juliet."

The model maps the ship with millimeter-scale precision, revealing individual rivets; the ship's serial number; and the 3-mile-long (5 km) debris field surrounding the vessel.

For experts studying the wreck, the scan comes just in time. The ship is slowly disintegrating as deep-sea microbes feast on its iron hull, and previous salvage operations have caused accidental damage to the ship. For example, one operation conducted in 2019 by the company the RMS Titanic Inc. destroyed the ship's crows nest while retrieving its bell.

"I have been studying Titanic for 20 years, but this is a true game-changer," Parks Stephenson, a Titanic expert, said in the statement. "We've got actual data that engineers can take to examine the true mechanics behind the breakup and the sinking and thereby get even closer to the true story of the Titanic disaster. For the next generation of Titanic exploration, research and analysis, this is the beginning of a new chapter."

Much of the wooden hull of a rare Elizabethan-era ship has been found in a flooded quarry in southeast England, hundreds of yards from the nearest coast.

Few vessels from this time have survived, so an analysis of the find may shed new light on a key period in seafaring, when the country rapidly expanded its trading links throughout Europe through its control of the English Channel.

"To find a late-16th-century ship preserved in the sediment of a quarry was an unexpected but very welcome find indeed," said Andrea Hamel, a marine archaeologist for Wessex Archaeology, which investigated the discovery on behalf of Historic England, a government agency dedicated to historical preservation. 

"The ship has the potential to tell us so much about a period where we have little surviving evidence of shipbuilding, but yet was such a great period of change in ship construction and seafaring," she said in a statement from Wessex Archaeology.

The remains of the ship were found in April in a flooded quarry being dredged for gravel on the Dungeness headland in Kent, about 60 miles (100 kilometers) southeast of London.

Related: 30 incredible sunken wrecks from WWI and WWII

Workers from the quarry firm CEMEX reported the discovery to local government officials, who then contacted Historic England to arrange specialist support and emergency funding to recover the remains, according to the statement. 

Moving coastline

The quarry site now lies about 1,000 feet (300 meters) from the nearest coast, but archaeologists think that the site formed part of the coastline in the 16th century and that the ship may have been abandoned there after it was wrecked on the rocky headland or discarded after it was no longer seaworthy.

The vessel has not been identified, but dendrochronological analysis of more than 100 timbers from the hull — based on the patterns of tree growth rings — show it was built from trees of English oak (Quercus robur) felled between 1558 and 1580.

According to the Wessex Archaeology researchers, that date estimate places the ship during a transitional period in shipbuilding in northern Europe, when the traditional "clinker" construction of overlapping hull planks was replaced by the stronger but heavier "carvel" construction developed in the Mediterranean, which used flush hull planks nailed to an internal frame.

The remains of the ship found at Dungeness had this newer carvel type of construction, and its introduction led to much heavier ships than had been built before, including those that would explore the Atlantic coastline of the New World in later decades, the researchers said.

Rare find

Wood quickly rots away in both air and water, and it usually lasts only a few years unless it is protected by an anaerobic layer of sediment — that is, a layer that protects it from oxygen. That means the wrecks of very few old wooden ships have survived to be found. And in the case of the Dungeness ship, the remaining hull timbers may have been covered by an anaerobic layer of silt beneath the floor of the quarry lake.

"The remains of this ship are really significant, helping us to understand not only the vessel itself but the wider landscape of shipbuilding and trade in this dynamic period," Antony Firth, head of marine heritage strategy at Historic England, said in the statement.

Using laser scanning and digital photographs, archaeologists are documenting what's left of the ship, and when the analysis is finished, the timbers will be carefully reburied in the quarry lake so they can continue to be protected by the silt layer. 

World War I (1914 to 1918) and World War II (1939 to 1945) saw some of the biggest naval battles and operations in history, and shipwrecks from this era are scattered across the world's oceans — around 15,000 ships, and over 500,000 people, were sunk during World War II alone, according to some estimates. Voyages by sea were the main means of travel at the time of the world wars, and control of the oceans was a primary goal in both conflicts.

Almost 80 years after the end of World War II, the wrecks of thousands of ships from World War I and World War II still lie on the seafloor, each with a unique — and often tragic — story behind it.

Here, we take a look at some of the most notable underwater wrecks from World War I and World War II.

1. Wreck from the Battle of Midway

The Japanese aircraft carrier Kaga is only the second wreck discovered from the Battle of Midway, the June 1942 clash against a Japanese attack that was decisively won by the U.S; the other is the wreck of the American aircraft carrier USS Yorktown. Bombs from U.S. warplanes tore apart the Kaga and set it on fire, and other Japanese warships eventually scuttled the carrier using torpedoes.

2. Dutch submarines near Malaysia

Two Dutch submarines that sank in Southeast Asia during World War II now seem to have disappeared, probably at the hands of illegal salvagers. One of the subs, HNLMS O 16, was sunk by a naval mine in the Gulf of Thailand in December 1941. The other, HNLMS K XVII, was sunk by bombs from Japanese warplanes in February 1942.

3. Sammy B in the Philippine Sea

The American destroyer USS Samuel B. Roberts, nicknamed the "Sammy B," was discovered in the Philippine Sea in 2022 at a depth of 22,916 feet (6,985 meters), making it the deepest known shipwreck in the world. It sank in October 1944 during the Battle of Leyte Gulf, one of the largest naval battles in history, after the ship was hit by shells from Japanese warships.

4. USS Johnston found deep underwater

Until the Sammy B was located, the world's deepest known shipwreck was that of the USS Johnston, a destroyer that was also sunk during the Battle of Leyte Gulf. The wreck lies 21,180 feet (6,456 m) below the ocean surface off the island of Samar in the Philippines, where it sank after an intense battle with Japanese warships.

5. Amphibious vehicles and warplanes

Several World War II wrecks lie on the seafloor near the Hawaiian island of Maui. They include amphibious assault vehicles used to train U.S. troops for major invasions of Pacific islands, as well as the wrecks of a number of warplanes, among them an F6F Hellcat fighter and an SB2C Helldiver bomber.

6. Discovered off North Carolina

Two World War II vessels that sank in July 1945 within minutes of each other and just a few hundred yards apart were discovered off North Carolina in 2014. The Allied merchant freighter Bluefields was part of a convoy when it was sunk by a torpedo from a German U-boat, and the U-boat itself, U-576, was sunk a few minutes later by the convoy's escort ships.

7. 'Ghost ships' rise again

The eruption of an underwater volcano near Tokyo in 2022 raised around two dozen "ghost ships" from the seabed near the Japanese island of Iwo Jima. The island was the scene of fierce fighting during the Battle of Iwo Jima in 1945; the "ghost ships" are mainly Japanese transport vessels scuttled after the battle by the victorious U.S. Navy.

8. American destroyer sunk by explosion

The wreck of the American destroyer USS Abner Read was discovered in 2014 near the island of Kiska, part of Alaska's Aleutian Islands and one of only two areas of U.S. territory briefly occupied by the Japanese during World War II. The ship was on patrol in August 1943 when it was sunk by a large explosion, probably from a Japanese naval mine.

9. Sea monster attack?

A World War I German U-boat supposedly attacked by a sea monster was discovered on the seafloor between Scotland and Ireland in 2016. According to British war records, the UB-82 was sunk by British patrol boats in April 1918. But an internet legend relates that the submarine's captain reported that the vessel was first attacked by a sea monster, which damaged it and prevented it from diving.

10. Sunken treasure

The wreck of a German steamship that was sunk in the Baltic Sea near the end of World War II may hold the precious panels from Russia's 18th-century Amber Room. The ornate room was built in a royal castle near St. Petersburg, but it was captured and stripped by the invading Germans in 1941. Researchers believe that the steamship may have been carrying the Amber Room panels and other fittings away from the city of Königsberg when it was sunk by Soviet warplanes in April 1945.

11. Shot-down warplane

In 2020, wreck divers confirmed the identity of the pilot of a warplane that was shot down in 1945 near the remote Japanese island of Iriomote. U.S. Marine 2nd Lt. John McGrath piloted the aircraft, an F4U-4 Corsair, during an attack on the island in the last stages of World War II. A member of McGrath's family dived to the wreck as part of the research.

12. Sunk American submarine

An American submarine, the USS Grenadier, that sank in 1943 was discovered by divers at the north end of the Strait of Malacca, between the Malay Peninsula and Sumatra, in 2020. It was sunk by a torpedo dropped from a Japanese warplane as the submarine attempted to attack two Japanese cargo ships near the Thai island of Phuket.

13. Polluting German warship

A German warship that sank in 1942 is still polluting the North Sea with toxic chemicals from its fuel and ammunition, according to a 2022 study. The patrol boat was sunk as it took part in Operation Cerberus, when it was part of a convoy escorting the cruiser Prinz Eugen and the battleships Scharnhorst and Gneisenau through the English Channel.

14. Sub sunk and then bombed

A Japanese submarine that was sunk in World War II and then bombed by a salvager 30 years later is now the subject of a virtual-reality study. The sub was sunk with depth charges from Australian warships off the coast of Darwin in 1942, and in 1977, it was damaged by explosives from a salvager who was attempting to force a deal for its recovery with Japan's government.

15. Sub on a secret mission?

The wreck of the British submarine HMS Urge was discovered in 2019 near the Mediterranean island of Malta. The sub disappeared in 1942 and became the subject of a theory that it sank during a secret mission to Libya. But researchers now think it sank after hitting a naval mine while making its way to the Egyptian port of Alexandria.

16. HMS Warrior damaged by gunfire

The British warship HMS Warrior — the "last shipwreck" from World War I's Battle of Jutland to be discovered — was found on the seafloor near Norway in 2016. More than 250 warships took part in the battle on May 31 and June 1, 1916; HMS Warrior was damaged by gunfire, and it sank as it attempted to make its way back to the U.K. 

17. Battlecruiser surprised and sunk

The wreck of the World War I battlecruiser Scharnhorst was discovered near the Falkland Islands in the southern Atlantic Ocean in 2019. The vessel had tried to lead an attack on the Falklands, but the German squadron was surprised and destroyed by a larger force of British warships. (A second German warship named Scharnhorst fought in World War II and was sunk near Norway in 1943.)

18. Foggy collision

The USS McCulloch was built as a revenue cutter in 1896 and saw action in the Spanish-American War; it was transferred to the U.S. Coast Guard in 1915, and then to the U.S. Navy in 1917, where it served as a patrol boat along the West Coast. But in 1917, it collided in thick fog with a passenger steamship and sank off the coast of California.

19. Australia's first WWI navy loss

The wreck of an Australian navy submarine that disappeared in 1914 was found off an island in Papua New Guinea in 2017. The HMAS AE1 was the first loss suffered by the Australian navy during World War I; it's now thought that the submarine mistakenly dived with a ventilation valve open, which flooded its engine room.

20. Seal hunting ship to patroller

In 2021, one of the U.S.'s most storied ships, the U.S. Revenue Cutter Bear, was discovered in the ocean southeast of Boston, where the ship sank as it was being towed to Philadelphia for its final voyage. The Bear started working as a commercial seal hunting vessel in 1874, but in the 1880s, it was purchased by the government to rescue sailors icebound in the Arctic. In 1918, it served as a relief ship during the Spanish flu pandemic; and it patrolled the Arctic in both World War I and World War II.

21. Torpedoed cruiser

In 2014, U.S. Navy and Indonesian navy divers explored the wreck of the USS Houston, a heavy cruiser that sank during the Battle of Sunda Strait in February 1942. More than 700 of the ship's crew were lost after it was struck by several torpedoes launched by Japanese warships; 368 survivors were taken prisoner, but 77 died in Japanese captivity.

22. Drought reveals Higgins boat in Lake Mead

In July 2022, the receding waters of Lake Mead near Las Vegas revealed the wreck of a World War II landing craft, also known as a Higgins boat. The vessel was one of 23,000 made for the U.S. and Allied militaries during World War II, and they carried Allied troops onto the beaches of Normandy on D-Day, June 6, 1944.

23. U-boat spotted by British bombers

Germany built increasingly advanced versions of its U-boats in both world wars, and the submarines were a crucial concern in the battle for control of the oceans. One of the most advanced U-boats, U-3523, set out from Denmark a few days before the end of World War II in Europe; experts think it was probably fleeing to safety. However, it was spotted in the North Sea by British bombers and sunk in May 1945.

24. Warship still sports Nazi swastika

In 2020, the wreck of the German warship Karlsruhe, which was torpedoed and sunk by a British submarine in 1940, was discovered by a Norwegian utility company near its undersea electricity cables in the North Sea. Images from a remotely operated vehicle show a medallion on the vessel decorated with a Nazi swastika.

25. Sunken light cruiser carried five brothers

The wreck of the American light cruiser USS Juneau was discovered in 2018 near Guadalcanal in the Solomon Islands. The ship was sunk by a Japanese torpedo during the Battle of Guadalcanal in November 1942. Among the 682 dead were five brothers from the Sullivan family of Waterloo, Iowa, who had received a dispensation to serve together.

26. Sunken freighter on a virtual-reality experience

One of the world's most famous dive sites, the wreck of the British freighter SS Thistlegorm in the Red Sea, is now a virtual-reality experience. German bombers sank the vessel in 1941 as it was carrying wartime cargo to Alexandria, Egypt, including tanks, train engines, trucks and motorcycles.

27. Six warships lost, possibly to illegal salvaging

At least six warship wrecks from World War II in the Java Sea near Indonesia have almost vanished after being illegally plundered for scrap metal by salvagers. These include three Dutch warships from what was then the Dutch East Indies, two British warships and an American submarine, the USS Perch, which was sunk by Japanese warships in March 1942. Southeast Asian nations are struggling to crack down on the illegal salvaging of metal from the region's numerous war wrecks.

28. Powerful battleships sunk

A legendary Japanese battleship that was sunk during the Battle of Leyte Gulf in October 1944 was found in the Philippines' Sibuyan Sea in 2015. The Musashi was one of the most powerful battleships ever built — a sister ship to the famous Yamato. Neither warship survived World War II.

29. German U-boat sunk during target practice

The wreck of a German U-boat given to the U.S. after World War I so its technology could be built into American submarines was found off the coast of Virginia in 2022. SM U-111 took part in the wartime German campaign to sink Allied shipping, but it surrendered after an armistice in 1918. The sub then crossed the Atlantic to the U.S. and was reverse-engineered before it was sunk by U.S. warplanes for target practice in 1921; it was then refloated and towed out to be sunk at its final resting place in August 1922.

30. Scuttled in Scotland

The wrecks from World War I's Imperial German Navy were located and mapped at Scapa Flow in Scotland's Orkney Islands in 2017. The entire German High Seas Fleet surrendered and was interned there after the World War I armistice in November 1918, but the warships were scuttled by their crews in June 1919, a few days before the signing of the Treaty of Versailles, which Germany's commanding admiral feared would give the ships to the British.

Archaeologists have discovered the remains of a mysterious vessel that could be one of Norway's oldest shipwrecks, during an effort to locate tons of unexploded ammunition dumped on the bottom of a lake near Oslo. 

Sonar images show the hull of the 33-foot-long (10 meters) wooden ship at a depth of about 1,350 feet (410 m) beneath the surface of Lake Mjøsa, about 60 miles (100 kilometers) north of the Norwegian capital.

What is known of the ship's construction suggests it was built up to 700 years ago, soon after the transition from Viking ships — which were almost the same at both ends — to medieval designs with a distinctive bow and stern, Øyvind Ødegård, a maritime archaeologist at the Norwegian University of Science and Technology (NTNU), told Live Science.

"We only have the acoustic [sonar] images of the wreck," he said. "But it appears from the data that there is the outline of something that possibly could be a stern — and if that's the case, then that doesn't really appear until the 1300s."

So far, bad weather and poor visibility have prevented researchers from investigating the wreck site with camera equipment, and it now looks like that won't be possible until conditions improve next year, Ødegård said.

Related: Radar uncovers Viking ship buried on Norway farm

The sonar images clearly show the distinctive frame of a "clinker-built" ship, a traditional Norse boatbuilding method in which the planks of the hull overlap, making the hull lighter. During the medieval period, that method was superseded by smoothly joined planks on stronger "carvel-built" ships, a Mediterranean innovation.

Historic lake

Ødegård is part of a project led by the Norwegian Defence Research Establishment (FFI) in collaboration with NTNU to locate and map hundreds of tons of surplus ammunition dumped in Lake Mjøsa from the 1940s until the 1970s.

The lake has also been a vital trade route between prosperous communities since at least the Viking Age (the eighth to 11th centuries), and Ødegård said he was drawn by the possibility of finding cultural objects in the depths. 

"Finding the wreck was almost a byproduct of the original mission to map dumped munitions," he said. "I expected to find some things — that's why I was participating in the project."

Lake Mjøsa covers more than 140 square miles (360 square km); of that area, only about 15 square miles (40 square km) have been mapped, using the FFI's Hugin autonomous underwater vehicle (AUV).

The AUV is equipped with sonar — sound navigation and ranging — which uses the reflections of sound pulses to make detailed acoustic images of the surroundings, even in almost lightless environments, such as the depths of the lake.

Mystery ship

Several acoustic images from the AUV have been used to make a three-dimensional model of the wreck.

Ødegård suggested that the vessel would have had a single mast with a square sail — much like a Viking ship — but that it seems to have sported a central rudder, rather than the traditional Viking rudder on the right side of the hull.

Ships of the same size and build were probably common on Lake Mjøsa in the medieval period, although the researchers won't be able to determine the vessel's purpose until they can explore it with cameras. "If we are lucky, there could be some cargo on board," Ødegård noted.

Also unknown is how much of the hull protrudes above the deep layers of sediment on the lake floor, which are partially invisible to the AUV's sonar equipment, he said. 

There may be even older wrecks to find in the lake. "If we are going to find a Viking shipwreck in Norway, then Mjøsa is probably the place with the most potential for such a find," Ødegård told Science Norway.

The wreck of a 17th-century Swedish warship called Äpplet — a sister ship of the famous Vasa, which sank only an hour into its maiden voyage in 1628 — has been discovered in the intricate waterways that lead to Stockholm, where it was deliberately sunk to protect the city from seaborne attacks in 1659.

The wreck is near the island of Vaxholm, but its exact location and depth are being kept secret; access to the site is controlled by the Swedish navy because the wreck is in a militarily sensitive area near the Swedish capital.

Archaeologists from Sweden's Museum of Wrecks and navy personnel made the first investigatory dives to the wreck in December 2021 and conducted a more thorough survey in the spring of 2022.

Jim Hansson, a maritime archaeologist at the museum who leads the project, said recent scientific analysis of several aspects of the wreck now leave no doubt that it is Äpplet. "It was about a month ago when all the pieces just fell together," he told Live Science. "We saw that this could not be any other ship — we were really thrilled."

Related: 15th-century Baltic warship served as a 'floating castle' for an intrepid king

The discovery of Äpplet ("The Apple") could help archaeologists better understand what caused the sinking of the Vasa, which was salvaged in 1961 and is now one of the leading museum attractions in Scandinavia.

The Vasa was named after the Swedish royal house and was among the most advanced warships of its time. It was 226 feet (69 meters) long and armed with 64 guns on two decks. Most of them were very heavy cannons that could fire a 24-pound (11 kilograms) ball.

But the ship sank on Aug. 10, 1628, after sailing just 4,265 feet (1,300 m) from an anchorage in Stockholm Harbor, when it foundered in a gust of wind in full view of a crowd of people. About 30 crewmembers died in the sinking.

Historical warships 

Hansson said the keys to identifying Äpplet were the tree rings visible in the timbers of the wreck, which showed conclusively that the ship was constructed from the same batch of wood as the Vasa, and accurate measurements of the hull that showed it had been built a few feet wider than the Vasa, which historical accounts attest.

Both the Vasa and Äpplet were designed by the Dutch-born shipwright Henrik Hybertsson. But he died in 1627, and the construction was completed by another Dutch-born shipwright, Henrik Jacobsson.

After Jacobsson completed the Vasa, he suspected it might have been made too narrow for its height, so he increased the width of the hull for Äpplet, which was completed a year later and launched in 1629, Hansson said.

Related: World's deepest shipwreck found — a US navy warship sunk in biggest sea battle of WWII 

Jacobsson also built two later warships of almost the same design: Kronan ("The Crown") and Scepter, both of which were made even wider. Scepter, especially, was very stable and a "good sailor," Hansson said. "So it took four ships to make a really good ship," he said.

The crucial problem with the Vasa appeared to be that it was too narrow for its height above the water, which allowed it to carry another deck for guns but also made it prone to leaning in heavy winds, he said.

"The king and the admirals wanted to have a heavy armament on the ship," Hansson said. But "if they had the lower gun ports open, and if they had too much ballast, and if it was windy … then it would be really unstable."

Deliberate sinking

The Äpplet wreck is important in its own right as an early 17th-century warship and will cast new light on the Vasa and the reasons for its sinking.

One of the most crucial features of the newfound wreck is that its hull is exposed in places where the Vasa's is not; that difference will enable archaeologists to study the construction of both ships without violating the legal preservation orders that surrounded the Vasa. 

"It has an enormous potential for us, for the simple reason that I'm not allowed to take Vasa apart," said Fred Hocker, director of research at the Vasa Museum. "But the structure of the hull is four or five layers of timber thick that I can't see and can't get to."

The wrecks of the two later ships in the same series, Kronan and Scepter, have not been found yet, "but we're on the trail," Hocker said.

Like Äpplet, they were deliberately sunk in the middle of the 17th century to protect against sea approaches on Stockholm by snagging the hulls of enemy vessels, he said. 

Hansson added that Sweden was engaged in wars with the Netherlands, Denmark and Poland during this time, and the decision to deliberately sink the ships meant that they continued to have a role in defense.

"They got a second history — they defended Sweden on the sea, and then they ended up on the seabed where they were still defending," he said.

The wreck of a Nazi patrol boat sunk by British warplanes in the North Sea in 1942 is still leaking hazardous chemicals 80 years later, according to new research.

A study published Oct. 18 in the journal Frontiers in Marine Science shows that pollutants from the historic shipwreck — including polycyclic aromatic hydrocarbons (PAHs) from its fuel, heavy metals, and traces of explosives — are affecting the microbiology and geochemistry of the seafloor around where it now rests; and the researchers suggest that the thousands of wartime wrecks in the North Sea, between Britain and the European continent, could similarly threaten the marine environment.

"The heavy metals can come from various sources — the metalwork inside the wreck itself can be a source of metal ions, as well as the fuel (coal), paint, and lubricants," project leader Maarten De Rijcke, a researcher at the Flanders Marine Institute in Belgium, told Live Science. "The PAHs and explosives are more clearly linked to the cargo of fossil fuels and munitions."

However, there are some signs that marine life is adapting to the wreck, with some bacteria possibly munching on the sunken ship's remains. 

Related: World's deepest shipwreck found — a US navy warship sunk in biggest sea battle of WWII

De Rijcke said in an email that the wreck of the V-1302 John Mahn was chosen for the study because its position in the North Sea gives average hydrological conditions for the coast of Flanders; it is away from shipping lines, with good visibility and at an accessible depth; and it was known to contain munitions, which had been mentioned by recreational divers.

He and his colleagues wanted to learn if such wrecks were still affecting the microbial communities and surrounding sediments of the seafloor where they lie, thereby giving the researchers a unique insight into the environmental threats they pose, according to a statement.

Historic wreck

The John Mahn was a German fishing trawler when it launched in 1927, but after World War II broke out in 1939 it was requisitioned by the German navy — called the "Kriegsmarine" under the Nazis — as a "vorpostenboot," or patrol boat, with the designation V-1302.

The Kriegsmarine based the vessel in the occupied Dutch port of Rotterdam, and in February 1942 it served in Operation Cerberus — a major naval action also known as the "Channel Dash" — as part of a convoy escorting the heavy cruiser Prinz Eugen and the battleships Scharnhorst and Gneisenau through the English Channel to ports in Germany.

But the V-1302 John Mahn was sunk by British bombers during the action, on Feb. 12, 1942; Twelve of its crew were killed, while 26 others were rescued by German ships nearby.

Although several other vessels were badly damaged during Operation Cerberus, V-1302 John Mahn was the only German ship sunk during the action. Its wreck now lies in the North Sea off the coast of Belgium, at a depth of about 115 feet (35 meters).

De Rijcke said the wreck is broadly typical of other World War II shipwrecks in the North Sea, although some are much larger and could pose a greater environmental threat.

"The munitions and fuel found on this wreck were in common use across all Kriegsmarine ships," he said. "A more heavily-armed destroyer or cruiser with the same munitions would be worth investigating, as our results show that the munition casings can be corroded through."

Leaking chemicals

The research team analyzed samples taken directly from the wreck's steel hull and the surrounding seafloor in July 2020, and kept frozen since then.

Their study showed that while many of the chemicals were hazardous, all were well below toxic levels after 80 years beneath the waves. "At these concentrations, they are all harmless," De Rijcke said.

The highest levels of metals like nickel and copper were found in the samples taken close to the ship's coal bunker — its supply of fuel — while the highest concentrations of PAHs were found in the samples taken closest to the vessel.

The analysis showed that the wreck had a relatively high level of biodiversity — fish, crabs and other crustaceans, molluscs, sea anemones, and marine plants, for example, use such wrecks as artificial reefs.

But it also showed that microorganisms on and around the wreck were adapting to the chemicals leaking from it and the metals of the vessel itself, and that some were even using them as food. "We see an increase of PAH-degrading bacteria near the coal bunker, indicating that some bacteria are benefitting from the availability of this chemical as a resource," De Rijcke said. 

The study is part of a project to assess the environmental risks from sunken wrecks, which will allow governments to prioritize the most hazardous wrecks for closer inspection, he said.

Andrew Turner, an associate professor of marine and environmental biogeochemistry at the University of Plymouth in the United Kingdom who wasn't involved in the study, explained that all sunken vessels release contaminants into the seawater, but the severity of the problem depends on how large they are and the particular chemicals involved.

"Unfortunately, we do not know how widespread the problem of sunken boats is," he told Live Science.

And Doug Helton of the Emergency Response Division of the National Oceanic and Atmospheric Administration (NOAA), said that although it could be expensive to assess the risk from a shipwreck, it would be less costly than dealing with an uncontrolled oil or chemical spill.

But "many are grave sites and historic, so caution is always advised," he told Live Science in an email. "Some may be best left alone." 

A team of shipwreck hunters has discovered an extraordinary sunken vessel off the East Coast of the United States: the wreck of a World War I German U-boat sunk by U.S. warplanes a century ago for target practice. 

According to an exclusive report by National Geographic, the team confirmed the identity of the wreck in early September as that of SM U-111, a submarine that served in the Imperial German Navy. After Germany agreed to an armistice in 1918, the U-boat surrendered to the British, who saved a handful of the early submarines to the U.S. to study and reverse engineer. In 1922, the U.S. Navy deliberately sank the vessel, but its exact location was not disclosed.

But in early July, wreck researcher Erik Petkovic and his colleagues found the SM U-111 with a remotely-operated underwater vehicle (ROV) at a depth of about 400 feet (120 meters) and about 40 miles (65 kilometers) off the coast of Virginia.

"We were lucky," Petkovic told Live Science, describing the live video images sent back to their research ship through the tether of the ROV. "We were on the bottom of the Atlantic Ocean, and we saw the wreckage. We panned the camera, and the conning tower was right there." (A conning tower is the raised platform above the top deck of a submarine.)

Related: WWI German sub spotted off French coast, 100 years after its crew surrendered

The SM U-111 was one of five German U-boats from World War I that were sunk in U.S. waters (there are also eight from World War II) and it's the last to be rediscovered. 

When the U-boat sank, the U.S. Navy thought the seawater at the location was much deeper, and that the vessel would fall to the seafloor about 1,600 feet (500 m) below the surface, Petkovic said.

But knowledge of the depths was imperfect 100 years ago, and so SM U-111 came to rest in relatively shallow water next to a deep abyss. "If it was one mile to the east, it was in the abyss and it never would have been seen again," Petkovic said.

Submarine menace

Germany built the SM U-111 in the northern port city of Kiel in 1916 and it joined the war at sea in early 1918. The submarine made three raids on commercial shipping vessels in the Irish Sea and the English Channel, and sank at least three Allied merchant ships.

"The first U-boat war from 1914 to 1918 often gets overlooked," Innes McCartney, a nautical archaeologist at Bangor University in the United Kingdom, told Live Science in an email. "But it is important to recognize that in comparison to World War II, the U-boats of the Kaiserliche Marine [Imperial German Navy] sunk twice the number of ships and sustained only 20 percent of the losses."

McCartney was not involved in the rediscovery of the SM U-111, but he's discovered other World War I U-boat wrecks.

"Importantly for the Allies, had it not been for the experience gained in 1917 and 1918 in particular, the campaign against the U-boats in World War II would have proven more of a challenge," he said.

After Germany agreed to the armistice in November 1918, the SM U-111 was surrendered to the British and then given to the U.S. Navy; and in April 1919 it set out for the U.S. with a crew of 32 U.S. sailors — 17 of whom had never been aboard a submarine before, Petkovic said.

To save time, the commander chose the shortest — and most dangerous — northern route across the Atlantic, which was strewn with icebergs and had claimed the R.M.S. Titanic seven years before.

In addition, the submarine had only German signage, so the U.S. crew didn't know how to operate the vessel's gyro-compass, and had to navigate with a magnetic compass; and a plug in an open valve made of a "hard, gummy substance," secretly installed by German saboteurs, dissolved in the seawater four nights into the voyage, flooding and almost sinking the vessel.

"It's really remarkable that they survived," Petkovic said. 

Related: Lake Mead dwindles, and a WWII-era 'swamp boat' emerges

U-boat wreck

After its arrival on the U.S. East Coast, SM U-111 was used to promote a final 1919 issue of war bonds in Brooklyn, and was then tested against the latest U.S. submarines. Eventually its engines and equipment were stripped out, and in June 1921 U.S. warplanes using it for target practice sank the German sub.

But the vessel was considered a navigation hazard at the location where it first sank; and so it was raised and towed into deeper water in August 1922, where it was sunk for the last time by opening its hatches and setting off an explosive depth-charge nearby. Its exact location was not publicly disclosed.

Petkovic had searched for the wreck of SM U-111 for several years, after noting that the other deliberate wrecks of U-boats in U.S. waters were found in shallower waters than expected. He said the key to the discovery was determining which U.S. Navy ship had towed the disabled U-boat to its final destination, and then getting access to its logbook. They found the wreck of SM U-111 almost exactly at the location described in the ship's logbook. "It was right on the money, really close to the numbers that we had," he said. 

Petkovic now hopes to dive to the wreck next summer, although it's at an extreme depth even for technical divers with the latest rebreather equipment, which recycles the gases divers exhale and allows them to stay underwater longer.

"It's pushing the limit in terms of rebreather technology and the limits of human endurance," he said. "But there are guys on our team that are capable of doing it… it's still a dangerous dive, but that is a goal of ours."

You can read more about the German U boat discovery on National Geographic. 

A 15th-century royal warship resting off the coast of Sweden once served as a "floating castle" for an intrepid king, according to new underwater investigation that revealed cannons, handguns, crossbows and the vessel's stern superstructure.

The new finds on the wreck of the Gribshunden — the flagship of King Hans (or John) of Denmark until it sank in 1495 — show the vessel plied the seas as a fearsome ship of war armed with dozens of guns and packed with soldiers.

It's thought that the Gribshunden was armed with up to 90 early cannons, although they were much smaller than the ship-smashing cannons of the late 16th century, and that they were complemented by armored soldiers firing handguns and crossbows from the ship's upper deck, forecastle and sterncastle — the tall superstructures built at each end of the ship. 

The 115-foot-long (35 meters) wooden ship was one of the first vessels designed to carry artillery. It also utilized the new "carvel" shipbuilding technique, imported to the Baltic from the Mediterranean, of joining the planks of the hull edge to edge on a wooden frame instead of overlapping them in "lapstrakes."

Related: $17 billion shipwreck near Colombia is remarkably preserved, new photos reveal

That meant the Gribshunden could be built larger and stronger than ships with lapstrakes, and so it could carry more in heavier seas.

"This is kind of a new technology," Brendan Foley, a maritime archaeologist at Lund University in Sweden who is leading the latest excavations, told Live Science. "It was designed to carry artillery, and King Hans uses the ship in a way that no other king does."

Royal flagship

From the mid-1480s, Hans frequently journeyed on the Gribshunden throughout his realm, often surrounded by a large royal fleet, Foley said, adding that the ship was intended to intimidate the king's rivals. 

The son of the previous Danish king, Hans ruled Denmark from 1481 and gained the crown of Norway in 1483, but Sweden didn't submit to his rule until 1497.

"His realm is Denmark and Norway, and he's trying to get Sweden to rejoin the Nordic Union," Foley said. "So Hans is sailing around on this ship all the time." (The Nordic Union of Denmark, Norway and Sweden was also called the Kalmar Union, after the town in Sweden where it was agreed in 1397.)

Hans embarked on the Gribshunden (which means "Griffin dog," although it originally seems to have been called "Griffon") for negotiations at Kalmar in 1495 when the ship mysteriously sank, supposedly after a fire broke out, at an anchorage just offshore near the town of Ronneby.

The king and his retinue were onshore at the time, but a witness to the disaster said many of the roughly 150 men onboard were killed.

Many of the ship's guns were probably salvaged soon after the sinking, Foley said; the latest excavations found only 14 gun carriages near the stern, but many more were likely situated near the bow.

A peculiarity of the eastern Baltic Sea is that it's too cold and brackish for infestations of shipworm (which is not a worm but a mollusk, Teredo navalis). Because of that, the wooden gun carriages are still intact, although the iron guns have rusted away, he said. 

But there was no sign of fire, so the ship probably sank quickly after being holed below the waterline, possibly because its stores of gunpowder had exploded. "It's one of the first ships carrying gunpowder, so they probably hadn't worked out standard operating procedures for safety," Foley said.

Related: Shackleton's Endurance shipwreck teeming with extreme creatures

Floating castle

Local divers rediscovered the wreck of the Gribshunden near Ronneby in the 1970s, beneath about 33 feet (10 m) of water. It was identified in 2013, and in 2015, archaeologists recovered several artifacts, including the figurehead of a person clutched in the jaws of a dog or dragon, Live Science reported at the time. 

Foley led dives to the wreck in August and September, during which the team recovered more artifacts and captured three-dimensional data for a digital reconstruction.

The wreck is considered a proxy for the ships from the Age of Exploration, such as those of Christopher Columbus and Vasco da Gama, which were built at about the same time but are now lost. "Nothing else like this has been found," Foley said.

The combination of guns and crossbows, as well as the remnants of shirts of mail armor that were also found, show the transition from earlier weapons to gunpowder, he added.

The larger ship's guns were mounted on swivels within their wooden carriages and fired projectiles about the size of golf balls. Meanwhile, the handguns were very simple — about 16 inches (40 centimeters) long, with projectiles like musket balls that were fired by touching a match to a hole in the back. "They were basically like a small cannon," Foley said.

Fritz Jürgens, a maritime archaeologist at Kiel University in Germany isn't involved in the study of the Gribshunden, but he's leading research into a rare 400-year-old ship discovered in the outer stretches of the Trave River in the western Baltic. He noted that the Gribshunden is the oldest carvel-built ship ever found in the Baltic and one of the oldest purpose-built warships ever discovered.

"In the Middle Ages and in the later Hanseatic period [when a trading bloc dominated the Baltic, from the 13th to 17th centuries], they took normal cargo ships and put archers on it," Jürgens said. "But the Gribshunden had artillery on the forecastle and sterncastle — it was specifically built for war."

Editor's note: Updated at 12:24 p.m. EDT to note that the shipworm Teredo navalis copes well with low salinity (brackish waters), and also with low water temperature; but the combination of these two factors is what stops shipworm infestations in the eastern Baltic Sea.

Originally published on Live Science.

Maritime archaeologists in northern Germany have discovered the wreckage of a 400-year-old cargo ship that "sank almost standing," escaped decay from ravenous shipworms and still has the barrels of lime it was carrying for the stone-building industry centuries ago. 

The ship, a rare discovery, is from the Hanseatic period, when a group of northern European trade guilds dominated the Baltic and North seas from the 13th to 17th centuries, Live Science previously reported. Wood quickly rots away underwater in this region, and few shipwrecks of this age have ever been found. But maritime archaeologists think the wreck survived beneath the waves because it was quickly engulfed and protected by a layer of fine mud carried there by the river Trave, which leads to the city of Lübeck about 5 miles (8 kilometers) inland.

The remains of the ship were first found in 2020 during a routine sonar survey by authorities of the navigable channel in the Trave. The vessel lies at a depth of about 36 feet (11 meters) in the predominantly saltwater outer stretch of the river, between Lübeck and the port of Travemünde at its mouth to the Baltic Sea.

The wrecked ship was between 66 to 82 feet (20 to 25 m) long and may have been a galliot, a single-masted cargo ship common during the Hanseatic period, Fritz Jürgens, the lead maritime archaeologist on the project and assistant chair of protohistory, medieval and postmedieval archaeology at Kiel University in Germany, told Live Science. At that time, the towns and guilds of northern Germany and elsewhere in Europe made up a successful bloc — the Hansa — that dominated trade throughout the Baltic and the North Sea.

Related: Treasure trove of gold and jewels recovered from a 366-year-old shipwreck in the Bahamas

The layer of river mud over the wreck may have prevented it from being colonized by Teredo navalis, a type of saltwater clam called "shipworm" that rapidly eats submerged wood, Jürgens said. The bivalve quickly destroys wooden wrecks in the western Baltic region, but it doesn't live in the colder waters of the eastern Baltic; as a result, centuries-old wooden wrecks like the one in the Trave are almost never found in the west, he said.

Quicklime cargo

About 150 wooden barrels found almost intact on or near the wreck indicate that the ship was carrying a cargo of quicklime when it sank in the late 17th century. Quicklime is made by burning limestone and is a crucial ingredient for the mortar used in stonework. 

"The source for this would have been Scandinavia — in the middle of Sweden or in the north of Denmark," Jürgens said. "We know that this cargo was coming from there, most likely to Lübeck, because northern Germany has no big sources of limestone." 

Historical research may have pinpointed the date of the shipwreck to December 1680. A letter from that date in the Lübeck historical archives shows that the voight, or bailiff, of Travemünde asked an unknown recipient to recover the cargo of a galliot that had run aground in the river. That fits with what is known of the Trave shipwreck, Jürgens said, including the results of a dating technique called dendrochronology, which revealed that patterns of tree rings visible in its timbers were from trees felled in the 1650s.

It's likely that the ship had been turning before its entry into Lübeck, when it ran aground on a shoal in the river — a shallow area that still exists today and still threatens ships that don't know about it. It's possible that 17th-century workers recovered some of the ships' cargo, causing the ship to refloat; but the vessel soon sank due to leaks caused when it struck the shoal, he said.

The submerged wreck and its cargo have now been photographed in place by Christian Howe, a scientific diver based in Kiel, and the entire ship is expected to be raised from the riverbed over the next few years so that it doesn't move again and present a danger to modern shipping in the region, Jürgens said.

Historic wreck

Lübeck was famous for shipbuilding in the Hanseatic period, so it's possible the ship was built there. But such vessels were common throughout the region at the time the ship sank in the Trave, so perhaps it was constructed elsewhere in Europe, said Manfred Schneider, the head of Lübeck's archaeology department and a leader on the project to salvage the ship.

Related: Head of Hercules and other treasures found on Roman 'Antikythera Mechanism' shipwreck

The wreck is notable for its remarkable state of preservation, not only due to the lack of infestation by shipworms and other marine organisms but also because of its weighty cargo.

"There are still about 70 barrels in their original location on the ship, and another 80 barrels in the immediate vicinity," Schneider told Live Science in an email. "The ship therefore sank almost standing and did not capsize." He added that archaeologists may uncover further archaeological finds in the sediment that fills the ship's interior.

Raising the ship from the riverbed will give archaeologists a chance to fully investigate the hull and its construction, and perhaps identify its origin. "The salvage will probably also uncover previously unknown parts of the wreck that are still hidden in the sediment," Schneider said, such as rooms for the ship's crew in the stern that may still hold everyday objects from the 17th century.

Although Lübeck was a center for Baltic trade during the Hanseatic period, very few authentic maritime objects from that time had survived, Schneider said, so the discovery of almost an entire ship from this era is remarkable. "We have something like a time capsule that transmits everything that was on board at that moment," he said. "It throws a spotlight on the trade routes and transport options at the end of the Hanseatic period."

Originally published on Live Science.

The 2,000-year-old Roman shipwreck that carried the Antikythera Mechanism — a precise mechanical model of the sun, moon and planets — is giving up new treasures, including a marble head thought to depict the Greek and Roman demigod Hercules.

Scientists and divers made the new discoveries after creating the first phases of a precise digital 3D model of the shipwreck, which sank near Antikythera, a Greek island in the southern Aegean Sea, in about the second quarter of the first century B.C. The digital model — which the scientists made with thousands of underwater photographs of the seafloor site, using a technique called photogrammetry —  could help in the search for more pieces of the mysterious geared mechanism, the team said.

The model has already enabled archaeologists to identify and remove several large boulders that tumbled over the wreck site after an earthquake, which occurred sometime after the ship sank. The removal of the boulders revealed an area that’s thought to be within the ancient ship's hull and contained the latest finds, including the massive marble head of a sculpture thought to represent the Greek demigod Herakles (Hercules in Latin), according to a statement by the expedition team. It’s almost certain that the head came from the headless sculpture of a human body that was found during the first expedition to recover objects from the wreck after it was discovered by sponge divers in 1900.

Related: The 25 most mysterious archaeological finds on Earth

The salvage divers working over 100 years ago also found the remains of the Antikythera Mechanism — now on display in at the National Archaeological Museum in Athens — so it's likely that both the statue and the mechanism were located in roughly the same area of the ship, Lorenz Baumer, a classical archaeologist at the University of Geneva in Switzerland and co-leader of the expeditions. told Live Science.

But "the site is quite big," he said. "It's some 50 meters [164 feet] across, and it's covered by rocks. It's possible that [more fragments] are hiding in the rocks, but they could be anywhere."

Ancient shipwreck

Baumer and his colleagues are taking part in the latest effort to investigate the Antikythera wreck, along with scientists from Greece's Ephorate of Underwater Antiquities; divers from the Greek coast guard; scientists at the Ca' Foscari University of Venice; and a dive team from the Swiss watchmaking company Hublot, which devised the underwater lifting equipment of pressurized airbags used to remove the overlying boulders, some of which weighed about 9.5 tons (8.5 metric tons).

Although the ship at Antikythera is thought to have been about 180 feet (55 m) long, according to the Woods Hole Oceanographic Institution in Massachusetts, the wooden hull has since rotted away, and only pieces of the rich cargo it once carried have been found, Baumer said.

It's not known how the ship sank — whether it tipped over and dumped its cargo out, for instance — or in what position it came to rest on the seafloor, he said. It now lies at a depth of about 150 feet, just off a northern point of the island. 

The excavations completed during the latest expedition, in May and June 2022, focused on a small area exposed after the boulders were lifted from the site. In addition to the head of the marble statue, the team found two human teeth within a glob of marine deposits and fragments of copper and wood.

Scientists hope to analyze isotopes in the enamel of the teeth. Isotopes are variations of chemical elements that have lost neutrons from radioactive decay, and can reveal the geochemistry of the environment when the teeth formed. The isotopes could help scientists determine a person's diet or place of origin, and the teeth might even contain fragments of DNA, Baumer said. Archaeologists will also look for more human remains where the teeth were found.

Mysterious mechanism

The ancient ship was filled with Greek artworks when it sank — it contained several bronze statues and more than 38 marble sculptures, including of horses — and it seems likely that it was being transported to Italy on behalf of wealthy Romans or to be sold to them, Baumer said.

Dives to the Antikythera wreck over the more than 120 years since it was found have recovered several bronze and marble sculptures, precious glassware and a bronze lyre that may have come from a statue of Eros (the Greek god of desire) or Apollo (the Greek god of the sun, music and knowledge). 

The latest excavations also found a marble base portraying the lower legs of a statue; bronze and iron nails; the lead collar from a wooden anchor; and several shapeless fragments of iron that will be examined with X-rays and other laboratory analytical techniques, Baumer said.

One of the goals of the latest project is to determine precisely where the fragments of the Antikythera Mechanism were found during the first salvage expedition in 1900 and 1901, Baumer added.

Only about half of the mechanism has been recovered, so it's possible that more pieces could be found. "We joke that we will find a box with 10 more of them," Baumer said.

Mike Edmunds, an astrophysicist at the University of Cardiff in the United Kingdom and the lead scientist on the multidisciplinary Antikythera Mechanism Research Project, said that finding more of the mysterious object could help resolve questions about an additional function of the mechanism that's hinted at by the Greek inscriptions on its surface.

It now seems that the mechanism's model of the positions of the sun and moon was supplemented by gears to show the positions of the major planets within the celestial zodiac. But that function may never have been implemented, or it may have broken, he said.

Edmunds thinks the Antikythera Mechanism is better described as an "ancient calculator" than as an "ancient computer," because it couldn't be programmed. 

But the mechanism was accurate enough to determine the months when solar and lunar eclipses might be expected to take place, in accordance with the Saros cycle shown by one of the spiral dials on its rear face. The Saros cycle is 18 years, 11 days, and 8 hours long, after which the sun, moon and Earth are at approximately the same positions relative to each other, and was known to ancient Babylonian astronomers, Edmunds said.

"It was very clever and displayed lots of things," he said. "It would be great if they do find more of it in the wreck."

Originally published on Live Science.

New images of one of the world's most valuable shipwrecks show its remarkable preservation on the seafloor off the coast of Colombia — while the search has revealed two more historic shipwrecks in the same area.

The latest photographs and video of the wreck of the San José treasure galleon were released by the Colombian navy on June 6.

The ship was loaded with an estimated $17 billion worth of gold, silver and jewels when it sank in 1708, and its wreck was only discovered in 2015. The navy used a remotely operated underwater vehicle (ROV) to examine the wreck; its precise location is being kept a secret to deter treasure hunters.

The new images show that the wooden hull of the San José is covered in marine growth — ocean species that colonize substrate and shipwrecks — but is still remarkably intact after more than 300 years beneath the waves.

A spokesperson for the Colombian navy said cannons, coins and gold bars can be seen lying exposed on the seafloor, as well as a delicate set of porcelain tableware in perfect condition. 

Related: Colombia moves to salvage immense treasure from sunken Spanish galleon

In many cases the preservation is so good that the searchers can read inscriptions on the objects. "With the inscriptions discovered, it was possible to determine the manufacturing sites of the ship’s cannons: in Seville and Cádiz, in the year 1655," said Adm. José Joaquín Amézquita, the Colombian navy's maritime director-general, said in a statement. "You also can see the different objects of gold, including the 'macuquinas' [a type of coin] and the date they were minted."

Experts think that the shipwreck and its artifacts may be so well preserved because the San José sank to a considerable depth — around 2,000 feet (600 meters) — far below the reach of the sunlight that sustains many marine organisms.

Navy experts also discovered two other wrecks on the seafloor nearby — one of a ship from the colonial period (from the arrival of the Spanish in about 1525 until the early 1800s) and the other of a roughly 200-year-old schooner. The origins of both ships are unknown.

Contested ownership

The San José wreck and its valuable contents are at the center of an international legal row. The Colombian government claims ownership of the shipwreck and all the treasures it contains, and the Colombian navy is monitoring the site on the seafloor, which rests near the Barú peninsula, south of Cartagena.

However, the ship belonged to the Spanish navy when it was sunk by British warships in 1708, and under international law Spain still owns the San José and everything it contains.   

In 2018, the United Nations Educational, Scientific and Cultural Organization (UNESCO) advised Colombia not to salvage the wreck, the Associated Press reported.

But Colombia's government has declared that the wreck and all its treasure belong to them, and it has asked prospective salvagers to register their interest in recovering it. 

Treasure ship

According to the Spanish naval history website Todo a Babor ("All to Port"), the San José was a 62-gun galleon of the Spanish navy. In 1708, it led a treasure fleet of three warships and 14 merchant vessels from Portobelo in Panama to Cartagena, a major port city on Colombia's Caribbean coast, where the ships intended to shelter during the approaching hurricane season before crossing the Atlantic Ocean to Europe. Historical records report that the San José galleon was laden with roughly 200 tons (180 metric tonnes) of gold, silver and jewels. 

But the convoy was intercepted in early June that year by British navy warships. During the ensuing battle, the San José exploded when its stores of gunpowder ignited. About 600 of the crew and passengers on board the galleon were killed.

The whereabouts of the San José wreck remained unknown until the 1980s, when an American salvage company claimed it had located the site and attempted to negotiate with the Colombian government for its recovery.

Colombia's government declined, however, and in 2015 it announced the San José wreck had been located independently by maritime archaeologists working with the Colombian navy. 

The wreck site's considerable depth makes recovery expensive and complex; so far, no physical steps have been taken to salvage the ship or its treasure.

Colombia’s president, Iván Duque, said that the monitoring of the wreck by the Colombian navy would guarantee its protection as a "world heritage site."

But he also hinted at his government’s assertion that Colombia owns the San José shipwreck and everything onboard it, adding that artifacts from the wreck would be displayed in museums.

"The idea is to recover it and have sustainable financing mechanisms for future extractions," Duque said. "In this way the treasure, the heritage of the San José galleon, is protected."

Editor's note: Updated at 9:41 a.m. EDT on June 28 to add that the 600 fatalities from the sinking of the San José galleon included passengers, not just crew members.

Originally published on Live Science.

Construction workers have found the battered remains of a 700-year-old ship under the streets of the Estonian capital of Tallinn.

Buried approximately 5 feet (1.5 meters) underground, the remnants of the ship are made of oak and are just over 78 feet (24 m) long with a beam, the ship's widest point, measuring about 29 feet (9 m) across.

"The original length of the ship was bigger, since the stempost [the vertical timber at the bow] is missing and the bow of the ship is damaged," Priit Lätti, a researcher at the Estonian Maritime Museum, told Live Science in an email. "The ship was probably built at the beginning of the 14th century," according to a dendrochronological analysis, an examination of the tree rings found in the ship's wooden remains, he said. The ship is, at first glance, very similar to other ships found in Europe from the same time period, he added.

Unearthed near Tallinn's Old Harbor three weeks ago, the ship was a significant find for archaeologist Mihkel Tammet, who had been observing a construction project. According to Lätti, when areas under heritage protection are being excavated, an archaeologist must be present. The Estonian Maritime Museum was notified of the ship's discovery to help provide more information and record the find.

Related: Explorers dive to deepest known shipwreck

The ship was not buried very deep, and as Lätti told Live Science, it was filled with sand. It's likely the sea gradually filled the boat over the centuries, as different layers of sand were visible, he said.

Since the discovery of the ship, there has been speculation that it is a Hanseatic cog, a cargo ship used for trade by the Hanseatic League. The league, a group of trade guilds from across Europe, dominated the seas between the 13th and 15th centuries. However, Lätti said it is too early in the excavation process to be able to accurately determine the origins of the ship.

"Very probably, it is a cargo ship," he said. "Since we do not yet know the origin of the timbers (the dendrochronological analyses are still preliminary, so I do not want to mention exact dates or first ideas about the origin of the timber) it is hard to tell the origin of the vessel." 

Researchers are also working to determine whether further artifacts found buried with the ship can be of use when determining the age of the boat. "Additional analyses have been taken; also the artefacts found aboard must be analysed to give more exact answers, Lätti added. "At the moment, only the bow area of the ship is excavated; the cargo hold was relatively empty. Now the excavations move to the aft area of the ship, which may contain more finds."

Other artifacts uncovered with the ship so far include a couple of wooden barrels, pottery, animal bones, some leather objects and textiles. The number of finds is expected to increase in the coming days as the aft part of the ship is excavated.

The discovery of the ship in such a well-preserved condition is significant, as it will help historians and archaeologists learn more about shipbuilding and trade in the Middle Ages, as well as what life was like onboard these ships.

"For Tallinn as an old merchant town, finding something like this is an archaeological jackpot," said Lätti, who specializes in studying harbors and shipwrecks. "The development of Tallinn is closely related to maritime trade, and while we know quite a lot about the merchants and merchandise, we still know relatively little about the ships they used."

Ships similar to this one have been discovered in the past. For example, the Bremen cog was found in Germany in 1962, and a medieval cargo ship was uncovered in Tallinn in 2015 and is now housed in the Estonian Maritime Museum.

The future of this ship, after it has been excavated, is still under discussion. But the aim is to remove it from the construction site where it was found and house it in a controlled environment and preserve it. Lätti described this as a "huge task." 

"The methods of transporting, preserving and conserving the ship are still discussed," he said, "because it is a very complex operation, and we are dealing with a very valuable archaeological object."

 Editor's note: Updated at 11:55 a.m. EDT on May 2 to correct a photo caption about the sternpost, which was incorrectly labeled as the stempost. 

Originally published on Live Science. 

A huge number of priceless treasures have disappeared from the historical record throughout the ages. These artifacts often go missing due to theft or under mysterious circumstances  during times of war or disaster, when they can't be protected or when military forces decide to take those treasures as a trophy. Sometimes treasures are recovered, but many are still missing.

Here are some lost treasures that have never been found. A few of these artifacts are now likely destroyed but some may still exist and one day be recovered.

Stolen Aztec treasure

The Aztec Empire in Mexico was thriving in the early 16th century, but its ruler, Montezuma, met his downfall when Hernán Cortes and his fellow Spanish conquistadors arrived in 1519. They made Montezuma their puppet ruler, and he died in 1520 in unclear circumstances. In the face of an Aztec rebellion, Cortes and his forces tried to sneak away from the Aztec capital of Tenochtitlan in the cover of night on June 30, 1520 with a huge haul of Aztec gold. But one of their vessels sank in a now dried-up canal that fed into Lake Texcoco, resulting in the death of many Spanish and the loss of some of the gold.

That night became known as "La Noche Triste," or the "Night of Sadness," to the Spanish. The Spanish returned a few months later to retrieve the lost gold, but they recovered only a portion of it. Some of that gold was found recently when a construction worker unearthed a centuries-old gold bar in Mexico City — which stands where the Aztec capital and its surrounding waters once lay — but much of the gold is still missing.

The Amber Room

The Amber Room was constructed in the Catherine Palace in the 18th century in Tsarskoe Selo, near St. Petersburg. The room contained gold-gilded mosaics, mirrors and carvings, along with panels constructed out of about 1,000 pounds (450 kilograms) of amber. Tsarskoe Selo was captured by Germany in 1941 during World War II, and the room's panels and artwork were disassembled and taken to Germany. They haven't been seen since, and it's possible they are now destroyed. Today, the Catherine Palace hosts a re-creation of the Amber Room.

Sarcophagus of Menkaure

The pyramid of Egyptian pharaoh Menkaure is the smallest of the three pyramids constructed at Giza around 4,500 years ago. In the 1830s, English military officer Howard Vyse explored the Giza pyramids, at times using destructive techniques (his use of explosives being the most notorious) to make his way through the structures. 

Vyse made a number of discoveries at Giza, including an ornate sarcophagus found in Menkaure's pyramid. Vyse tried to ship the sarcophagus to England in 1838 aboard the merchant ship Beatrice, but the ship sank during its journey and took the ornate sarcophagus down with it. If the Beatrice is ever found, it may be possible to retrieve the ancient sarcophagus. 

Ark of the Covenant

According to the Hebrew Bible, the Ark of the Covenant was a chest that held tablets engraved with the 10 Commandments. The chest was kept in a temple in Jerusalem in ancient Israel that was said to have been built by King Solomon. This temple, sometimes called the First Temple, was the most sacred site on Earth for the Jewish people, but it was destroyed in 587 B.C. when an army from ancient Babylon, led by King Nebuchadnezzar II, conquered Jerusalem and sacked the city. It's unclear what happened to the Ark of the Covenant, and its location has long been a source of speculation.

Honjo Masamune sword

The Honjo Masamune is a sword that was supposedly created by Gorō Nyūdō Masamune, who lived from 1264 to 1343 and is considered by many to be the greatest sword maker in Japanese history. The sword is named after one of its owners, Honjo Shigenaga, who took it as a prize after a 16th-century battle. The sword later came into the possession of Tokugawa Ieyasu, who became the first shogun of Japan after winning a series of wars in the 16th century.

The sword passed down through the Tokugawa family until the end of World War II, when the sword was turned over to American authorities during the American occupation of Japan, as they were concerned that the sword, and others like it, could be used against the Americans. But the sword never reappeared. It's possible that U.S. soldiers destroyed the sword, along with other captured Japanese weapons; or they may have brought the sword to America, meaning it could be recovered.

Lost Library of the Moscow Tsars

The Library of the Moscow Tsars supposedly contained a vast collection of ancient Greek texts, as well as texts written in a variety of other languages. The rulers of the Grand Duchy of Moscow supposedly built the library by 1518, and in the 16th century prince Andrey Kurbsky wrote of a meeting between the philosopher Maximus (1475–1556) and the grand prince of Moscow Vasili III (1479-1533) in which the grand prince showed Maximus a massive number of Greek books wrote, David Arans, a scholar, in an article published in 1983 in the Journal of Library History. 

There are claims that Ivan IV, better known as Ivan the Terrible, who lived from 1530 to 1584, somehow hid the library's texts. There have been many attempts over the centuries to find this "hidden library," but so far the searchers have come up empty-handed. Regardless of whether or not this hidden library existed, a number of ancient texts written in Greek and other languages are located in archives in Moscow and St. Petersburg, historian Patricia Kennedy Grimsted wrote in her book "Archives in Russia: A Directory and Bibliographic Guide to Holdings in Moscow and St. Petersburg" (Routledge, 1997).

Crown jewels of Ireland

Stolen in 1907 from Dublin Castle, the "crown jewels of Ireland" were "not connected with any coronation ceremony and included no crown. Rather, they comprised a jewelled star of the Order of St. Patrick and a diamond brooch and five gold collars of that order, all Crown property," Tomás O'Riordan, a historian and project manager at University College Cork, wrote in an article published in 2001 in History Ireland magazine. "[The] Order of St. Patrick was founded in 1783, to reward those in high office in Ireland and Irish peers — referred to as Knights' companions — on whose support the government of the day depended," O'Riordan wrote. 

Britain controlled Ireland at the time these "crown jewels" were created in 1783. The jewelry was made from 394 stones taken from Queen Charlotte's jewelry and an Order of the Bath badge. Queen Charlotte was the wife of King George III. The jewels also held rupees from a Mughal emperor and possibly precious stones provided by a sultan of Turkey, O'Riordan said. 

The jewels were kept in a library, and lax security was blamed for making the robbery possible. Who stole the jewels and what happened to them remain a mystery. A wide range of people have been suspected of pulling off the heist, including Francis Shackleton, brother of the famous explorer Ernest Shackleton, although nothing was ever proved.

Sappho's lost poems

The Greek lyric poet Sappho, who lived in the seventh century B.C., was the Shakespeare of her day. She was highly regarded by the ancient Greeks, who considered her to be one of the finest poets. Unfortunately for us, few of her poems still survive. In 2014, however, sections of two never-before-seen poems by Sappho were revealed by University of Oxford papyrologist Dirk Obbink. One poem talks about her brothers, while the other tells of unrequited love. 

Their provenance is unclear. In 2021 Brill retracted an article written by Obbink that detailed its provenance and right now it is uncertain where exactly they come from.

Dead bishop's treasure

In 1357, a ship called the São Vicente set sail from Lisbon in Portugal to Avignon in France, carrying treasures acquired by Thibaud de Castillon, the bishop of Lisbon who had recently died. The treasures included gold, silver, rings, tapestries, jewels, fine plates and even portable altars. While sailing near the town of Cartagena, in modern-day Spain, the São Vicente was attacked by two heavily armed pirate vessels, whose crew seized the treasure. 

One pirate ship, commanded by a man named Antonio Botafoc (which in the languages used at the time in Iberia means "fire blast" or "fire fart") was later captured after it ran aground. However, the other pirate ship, commanded by Martin Yanes, appears to have made a clean getaway. What happened to Yanes, his pirate crew and the stolen treasure is unknown.

The Just Judges

The "Just Judges" panel is part of the Ghent Altarpiece, a 15th-century work of art painted by Hubert and Jan van Eyck in Saint Bavo's Cathedral in Ghent, Belgium. The panel shows a number of characters, whose identities are uncertain, on horseback. Philip the Good, who was duke of Burgundy at the time the altarpiece was created, is likely one of the characters. 

The panel was stolen in 1934 and has never been found. However, despite the passage of time, new tips continue to come in, and the case file — which is now more than 2,000 pages long — is still active, Noah Charney, an art historian, wrote in an article published in The Guardian in 2013. There had been numerous other attempts to steal the Just Judges panel and other parts of the Ghent Altarpiece prior to the 1934 theft.

Florentine diamond

The yellow 137-carat Florentine Diamond was likely from India that may have made its way to Europe by the end of the 15th century. How and when it got to Europe is a matter of debate. One story is that Charles the Bold who was the Duke of Burgundy from 1467-1477, had it cut from a larger diamond and was so enamored with the Florentine Diamond that he even carried it with him into battle and was supposedly killed with it on him. 

After World War I the last emperor of Austria-Hungary, Charles I, fled with it to Switzerland where he put it in a bank vault and entrusted it to an Austrian lawyer named Bruno Steiner, who was supposed to help the deposed royal family sell it and other royal jewels, wrote historian Gordon Brook-Shepherd in the book "Uncrowned Emperor: The Life and Times of Otto Von Habsburg" (Bloomsbury, 2007). It's unclear what happened next. A news report published in 1924 indicated that Steiner was arrested, charged with fraud and acquitted. It's possible that the Florentine Diamond was recut and is now a series of smaller diamonds.

Lost da Vinci mural

In 1505, Leonardo da Vinci painted a mural depicting the 1440 victory of the Italian League (led by Florence) over Milan in the Battle of Anghiari. The mural, created in the Palazzo Vecchio (the town hall in Florence), disappeared in 1563, when the hall was remodeled by painter and architect Giorgio Vasari. 

In 2012, a team of art experts announced they had discovered evidence that the mural was not destroyed and that Vasari had simply painted his own mural over da Vinci's work. The team had been doing scientific tests on the mural for years and had published a few of their studies including a radar study published in the journal NDT & E International in 2005. 

However, the team's results were never confirmed, and the research was put on indefinite hold later that year. In 2020, a different team of researchers contended that da Vinci had never painted the mural to begin with, although this claim is also disputed. Ultimately, what became of the mural — and whether it even existed — is a subject of debate. 

Menorah from the Second Temple

Between roughly A.D. 66 and 74, Jewish rebels fought against the Roman army in an attempt to free Israel from the Roman Empire's control. In A.D. 70, the rebels suffered a critical blow as Jerusalem was captured by a Roman force led by Titus, a general who would later become a Roman emperor. The Second Temple, at that time the most important religious site for Jewish people, was destroyed, and the Roman army carried its treasures back to ancient Rome. Those treasures included the temple's menorah — a lamp stand with six branches.

The Arch of Titus, located close to the Colosseum in Rome, includes a scene depicting the menorah being carried to Rome; in the scene, the menorah appears as a massive object, almost as big as the soldiers carrying it. The fate of the menorah after it arrived in Rome is unclear. 

Copper scroll treasures

Perhaps the most unusual Dead Sea Scroll discovered in the Qumran caves in the West Bank is a text engraved on a sheet of copper that discusses the location of a vast amount of hidden treasure. This Copper Scroll, as it is called, is in a museum in Jordan. Whether the ancient writer of the scroll was describing a real or legendary treasure is a source of debate among scholars. At the time the scroll was written, around A.D. 70, the Roman army was in the process of defeating Jewish groups that were rebelling against Roman rule; the Roman army had taken Jerusalem and destroyed the Second Temple. 

Some scholars have speculated that the treasures referred to in the Copper Scroll could be real treasures that were hidden before the Roman army destroyed the temple. Other scholars have argued that the amount of treasure discussed in the Copper Scroll is so vast that it must be the stuff of legend.

Isabella Stewart Gardner Museum stolen art

On March 18, 1990, two thieves dressed as police officers broke into the Isabella Stewart Gardner Museum in Boston, Massachusetts, and stole 13 works of art valued at about $500 million. They included three works by the Dutch painter Rembrandt and five works by the French artist Edgar Degas. The thieves' identity is still unknown, and the artwork has never been recovered. It's possible that the thieves who stole the works of art are now dead and the paintings are severely damaged or destroyed. Despite the high value of the art, it would be difficult to sell as it is well known, and any buyer could easily determine that it was stolen and end up facing criminal charges themselves. 

Peking Man

In 1923, the fossils of a hominid that is sometimes called Peking Man (a form of Homo erectus), who lived between 200,000 and 750,000 years ago, was discovered in a cave near the village of Zhoukoudian, close to Beijing (which at that time was called Peking). The fossils disappeared in 1941, during the Japanese invasion of China, andhe their location today is unknown. Some scholars have speculated that the fossils were lost at sea while being transported to the United States (in an effort to save them from the invasion); others think they may actually be located under a parking lot in China. 

Q source

Q Source, as modern-day scholars call it, or sometimes Q, is a hypothetical first-century A.D. text that contains a number of sayings attributed to Jesus. If it existed, scholars believe that Q source was used by ancient writers to help craft the gospels of Matthew and Luke. The existence of Q Source is based partly on the fact that several passages in Matthew and Luke are identical. 

While the Gospel of Mark is believed to be a source for both Matthew and Luke, some passages included in both Matthew and Luke are not in Mark. Some scholars believe that those passages are from another source, which they call "Q Source." ("Q" stands for "quelle," which means "source" in German.) The problem is that no copy of Q Source, if it really existed, is known to survive. Some recent scholarship suggests that the Gospel of Marcion, a second-century non-canonical text, may contain parts of this Q Source. 

Nazi gold

According to legend, near the end of the World War II, a Nazi force led by SS officer Ernst Kaltenbrunner sank a vast amount of gold into Lake Toplitz in Austria to keep it from being captured by the invading Allied forces. Since that time, numerous searches have been undertaken, but, so far, no gold has been found. 

It's possible that the story is a just legend and that in reality no gold was sunk into the lake; however, some researchers have noted that the lake has poor visibility and a vast amount of logs and debris that make attempts to locate any gold both difficult and dangerous. Some divers have been killed trying to find gold in the lake's waters.

Lost Raphael painting

The Italian painter Raphael Sanzio, often simply called "Raphael," who lived from 1483 to 1520, painted this striking "Portrait of a Young Man." The identity of the person in the painting and the exact date when Raphael made it are both unknown. The painting was owned by the Czartoryski Museum in Krakow, Poland, in September 1939 when the German army invaded Poland. Nazi officials stole the painting from the museum and intended to put it in the planned Führermuseum in Linz (the Linz Art Gallery), Austria, the Monuments Men Foundation noted on its website.

The Führermuseum was never built, and the painting was last seen in Hans Frank's chalet in Neuhaus on lake Schliersee, Germany, in January 1945. Frank was a Nazi official who was put in charge of occupied Poland, where he oversaw numerous war crimes and the murder of Poland's Jews. After World War II, he was put on trial, sentenced to death and executed, but Raphael's painting has never been found.

Royal casket

In 1800, Poland's Princess Izabela Czartoryska created the so-called royal casket, which was a collection of artifacts from the royal families who had ruled the country. These artifacts included jewels worn by the kings of Poland, works of art and other mementos. Poland had ceased to exist as an independent state in 1795, having been divided up among the various other powers in the region. The royal casket would eventually fall victim to another group of invaders — it was seized by Nazi Germany after it invaded Poland in September 1939. The casket's contents are now lost.

Love's Labour's Won

William Shakespeare is known to have written the play "Love's Labour's Won," though no copies survive today. It may be a sequel to "Love's Labour's Lost," a comedy that Shakespeare penned in the 1590s. Documents in the 1590s and 1600s indicate that "Love's Labour's Won" had been published by 1598 and was still being sold in 1603, although no surviving copies have been found, William Carroll, an English professor at Boston University, wrote in the preface to a republished edition of "Love's Labour's Lost" (Cambridge University Press, 2009). 

Some scholars believe that records of "Love Labour's Won" refer to another play by Shakespeare called "Much Ado About Nothing," which is well known and is still performed today. One Royal Shakespeare Company production even retitled a performance (which can be seen on YouTube) of "Much Ado about Nothing" to "Love Labour's Won" based on this theory.

First-century gospels

The oldest surviving copies of the canonical Christian gospels — Mark, Luke, Matthew and John — date to the second century A.D. However, many scholars believe that some of these gospels were initially written in the second half of the first century A.D. This has led to several questions — do any copies survive from the first century? If so, how could we determine their date?? 

In 2015, scholars reported that they had found a fragment of the Gospel of Mark within the remains of a mummy mask, which they believe dated to the first century. However, after the text was published in a 2018 edition of the journal The Oxyrhynchus Papyri, it turned out that the text dated to the second or third century. 

Michelangelo's Mask of a Faun

This marble "Mask of a Faun" — a faun being a half-human, half-goat mythological creature — has been attributed to the Italian artist Michelangelo di Lodovico Buonarroti Simoni, often simply called "Michelangelo," who lived from 1475 to 1564. The Bargello Museum in Florence, Italy, owned the mask, but it was stolen in 1944 from Castello di Poppi, a castle in Tuscany. 

The thieves? Soldiers from the German army's 305th division that was attached to the German 10th Army, the Monuments Men Foundation noted on its website. The soldiers stole the mask sometime between Aug. 22 and Aug. 23, 1944, and placed it in a truck. "After a short stop in Forli, Italy, the 10th Army truck containing this work of art and others continued on Aug. 31," the foundation's website said. This appears to have been the last time it was seen and the mask's present location is unknown.

Caravaggio's Nativity

The "Nativity with St. Francis and St. Lawrence" was created in 1609 by the Italian painter Michelangelo Merisi da Caravaggio, who lived from 1571 to 1610. It shows the birth of Christ, with the infant Jesus lying on a haystack — a scene that highlights the poverty of his birth, according to scholars. The painting was stolen in 1969 when it was in a chapel in Palermo, in Sicily, Italy. The painting was never found, and it remains unclear who stole it. It's long been suspected that members of the Sicilian mafia carried out the heist. In 2015, a replica of the painting was unveiled in the chapel where the original was stolen.

Missing Romanov Easter eggs

Between 1885 and 1916, the jewelry company Fabergé, run at the time by the Russian jeweler Peter Carl Fabergé, made ornately decorated "Easter eggs" for the Russian imperial family.

These eggs "were the ultimate achievement of the renowned Russian jewelry house and must also be considered the last great commissions of objects d'art,"Fabergé notes on its company website. "Ten eggs were produced from 1885 to 1893, during the reign of Emperor Alexander III; 40 more were created during the rule of his dutiful son, Nicholas II, two each year, one for his mother, the dowager, the second for his wife," .

The Russian Revolution in 1917 led to the execution of Nicholas II, the last czar of Russia, along with much of the Romanov family. In the aftermath of their deaths, some of the eggs went missing and are still unaccounted for today; rumors claim that some of them are in private collections around the world. It's possible that some could now be in the United States — documents have come to light showing that shipments of antiques and artifacts worth an estimated $164 million were shipped from the Soviet Union to the U.S. at the end of the Cold War. 

Jules Rimet trophy

The Jules Rimet trophy was a prize that was awarded to the winning team of the soccer World Cup tournament. The trophy — named for Jules Rimet, founder of the World Cup — was sculpted by Abel Lafleur and had "a depiction of the goddess of victory holding an octagonal vessel above her head, produced in gold with a base of semi-precious stones," FIFA, the international governing organization of soccer, said on its website.

The trophy was first awarded in 1930 at the inaugural World Cup and passed from winner to winner every four years; but in 1970 Brazil won the competition for the third time. According to FIFA rules, the first team to win the World Cup three times would gain permanent possession of the Jules Rimet trophy. The cup was therefore sent to Brazil and a new World Cup trophy was created.

In 1983, the cup was stolen in Rio de Janeiro and hasn't been seen since. The thieves may have melted down the cup, which was made largely of gold and weighed about 13 pounds (6.1 kilograms). 

This wasn't the first time the Jules Rimet trophy had been stolen. In 1966, the trophy was taken from a Methodist hall in London. The trophy was recovered a week later when it was discovered by a dog named Pickles and its owner, David Corbett, who found it lying in a street in south London wrapped in newspaper and string, according to FIFA's website. The thief or thieves of this robbery were never found. 

Treasures of Nimrud

The ancient city of Nimrud is located in modern-day Iraq and was the capital of the Assyrian empire during the reign of Ashurnasirpal II, who ruled from 883 to 859 B.C. He built a new palace at Nimrud along with other amenities. Recent history has not been so kind to Nimrud. The terrorist group sometimes called the Islamic State group (also known as IS, ISIS, ISIL or Daesh) captured the ancient city in June 2014 during a military offensive; it wasn't recaptured until November 2016. 

By then, IS had blown up part of the city and used bulldozers to destroy and dig up other portions. Looting also took place in the period after the ancient city was retaken, when little security could be provided. While many treasures at Nimrud have been destroyed, others are damaged and can be reconstructed, and still others may be rediscovered on the black market.

George Mallory's lost camera

British explorers George Mallory and Andrew Irvine disappeared on June 8, 1924, while nearing the top of Mount Everest. A storm may have doomed their final push to climb the mountain. No one subsequently succeeded in reaching the summit until 1953, when a team led by Edmund Hillary became the first to climb Mount Everest. One question that remains unanswered is whether Mallory and Irvine managed to reach the top before they died. 

Mallory's body was discovered in 1999; evidence suggests he was killed by a fall. Irvine's body has never been found. If Irvine's body is discovered, it's possible that the camera Mallory and Irvine took with them will also be found. If the film in the camera is still preserved then it's possible it could be developed, and the question of whether Mallory and Irvine made it to the top of Everest before dying can finally be solved.

Michelangelo's Leda and the Swan

Michaelangelo's painting "Leda and the Swan" depicts a scene from ancient mythology where the god Jupiter, taking on the appearance of a swan, seduces Leda, the queen of Sparta. According to myth, Helen of Troy was one of their offspring. Michaelangelo's original painting is now lost, and only a small number of copies made by other people survive. 

The copies show that Michelangelo's painting was quite erotic, with a fully nude Leda shown, having sex with Jupiter, who is in the form of a swan. It's not known how exactly Michelangelo's painting became lost, but one possibility is that, over the past 500 years, some viewers found its erotic nature to be too much and it was destroyed at some point.

The Life of General Villa

The "Life of General Villa" is a lost film that depicted the Mexican revolutionary general Francisco "Pancho" Villa ( 1878-1923), who fought a series of battles against Mexico's leaders. While the film was heavily fictionalized, it featured footage of real-life battles fought by Villa's forces. Villa himself signed a contract with the Mutual Film Corporation (the maker of the movie) that allowed filmmakers to film him and the real-life battles fought by his troops in exchange for a share of the movie's earnings. While the film was released and shown publicly, it is now lost. 

Villa became an enemy of the United States not long after the film's release, when his troops crossed into New Mexico and killed several Americans. A U.S. military expedition into Mexico in 1916 failed to hunt him down, although he was assassinated in 1923, it may have been ordered by some of Mexico's leaders.

World's first feature-length film

The "Story of the Kelly Gang," released in Australia in 1906, is regarded by many as the world's first feature-length film. Running at over an hour long, the movie depicted the story of the 19th-century outlaw Ned Kelly (1854-1880) and his gang. The film was a huge success, film historians Sally Jackson and Graham Shirley wrote in an article on the National Film & Sound Archive of Australia's website. 

The film "opened in Melbourne on Boxing Day 1906 and went on to enthrall audiences across the country," Jackson and Shirley wrote. "By late 1907, the film had screened in New Zealand and England, where it was billed as 'the longest film ever made.'"

The film's depictions of a criminal gang earned it some notoriety. "Reports of crime and censorship followed screenings around the country. In May 1907, the film inspired five local children in the Victorian town of Ballarat to break into a photographic studio to steal money, after which they bailed out a group of schoolchildren at gunpoint," Jackson and Shirley wrote. "In April, the Victorian Chief Secretary banned the film from Benalla and Wangaratta, two towns with strong Kelly connections." 

Unfortunately, the film was never properly preserved, and by the 1970s, only "some publicity material and a few photographs" remained, Jackson and Shirley noted. Discoveries of bits of the film, along with restoration work, have allowed for about a quarter of the film to be revealed, but much of it remains lost.

The wreck of a 19th-century whaling ship has been identified on the sea bottom in the Gulf of Mexico. Its discovery was announced Wednesday (March 23) in a statement released by representatives of the National Oceanic and Atmospheric Administration (NOAA) and their partners in the expedition. 

Researchers on board NOAA Ship Okeanos Explorer spotted the wreck on Feb. 25 at a depth of 6,000 feet (1,800 meters). They used a remotely operated vehicle (ROV) to explore a seafloor location where the shipwreck had previously been glimpsed, but not investigated, in 2011 and 2017, and their search received additional guidance via satellite communication with a scientific team onshore, according to the statement. 

A team of experts then confirmed that the vessel was the Industry, which sank May 26, 1836, while the crew was hunting sperm whales. It was built in 1815, and for 20 years, the 64-foot-long (19.5 meters) ship had pursued whales across the Gulf, the Atlantic Ocean and the Caribbean, until a storm breached its hull and snapped its masts.

Though 214 whaling voyages crisscrossed the Gulf from the 1780s until the 1870s, this is the only known shipwreck in the region, NOAA representatives said.

The crew list for Industry's last voyage was lost at sea, but past ship records show that among Industry's essential crew were Native American people and free Black descendants of enslaved African people. The discovery of the wreck could offer important clues about the role that Black and Native American sailors played in America's maritime industry at the time, U.S. Deputy Secretary of Commerce Don Graves said in the statement. 

Related: In photos: Searching for Shackleton's Endurance shipwreck

"This 19th-century whaling ship will help us learn about the lives of the Black and Native American mariners and their communities, as well as the immense challenges they faced on land and at sea," Graves said.

Life on a whaling ship would certainly have been challenging, with long hours, hard physical labor and poor food that was likely to be infested with vermin, according to the New Bedford Whaling Museum in Massachusetts. Living conditions could also be extremely unpleasant; a whaler's account from 1846 described the crew's quarters, known as the forecastle, as "black and slimy with filth, very small and hot as an oven," J. Ross Browne wrote in the book "Etchings of a Whaling Cruise," according to the museum.

"It was filled with a compound of foul air, smoke, sea-chests, soap-kegs, greasy pans, [and] tainted meat," Browne wrote.

A deep dive

NOAA's Okeanos Explorer collects data on unknown or little-explored seafloor regions of the deep ocean, mapping seamounts and discovering mysterious forms of elusive marine life at depths from 820 to 19,700 feet (250 to 6,000 m), according to NOAA. Past expeditions have revealed "mud monsters" in the Mariana Trench, the "most bizarre squid" a NOAA zoologist had ever seen, and a real-life SpongeBob and Patrick living side by side on the seafloor, Live Science previously reported.

Video from the ROV combined with Industry records enabled the scientists to confirm that they had discovered the long-lost whaling brig. Another clue that helped experts to identify Industry was that there was little onboard evidence of its whaling activities; when the ship was sinking, another whaling vessel visited the foundering Industry and salvaged its equipment, removing 230 barrels of whale oil, as well as parts of the rigging and one of the ship's four anchors, according to the NOAA statement.

"We knew it was salvaged before it sank," Scott Sorset, a marine archaeologist for the U.S. Bureau of Ocean Energy Management and a member of the expedition's shore team, said in the statement. "That there were so few artifacts on board was another big piece of evidence it was Industry." 

New research has also shed light on what happened to Industry's crew on that final voyage. Robin Winters, a librarian at the Westport Free Public Library in Massachusetts, unearthed an 1836 article from The Inquirer and Mirror (a Nantucket weekly newspaper) reporting that Industry's crew was rescued by another whaling ship and brought to Westport. That was a lucky turn of events for Industry's Black whalers in particular, who could have been jailed under local laws had they reached shore with no proof of identity, said expedition researcher James Delgado, a senior vice president at the archaeology firm SEARCH. 

"And if they could not pay for their keep while in prison, they would have been sold into slavery," Delgado said in the statement.

Originally published on Live Science.

The extraordinary underwater photographs of the newly-found wreck of the Endurance have also revealed some equally extraordinary creatures lurking in the dark and freezing depths of Antarctica's Weddell Sea.

Marine biologists that viewed the photographs have already spotted about half-a-dozen animal species, which underscores the wealth of life that can be found in even the most extreme environments.

"The wreck is amazing, but can we also talk about some of the Antarctic seafloor creatures that now call it home," Huw Griffiths, a marine biologist with the British Antarctic Survey, wrote in a Twitter thread posted on Wednesday (March 9) .

Giffiths noted the photographs show filter-feeding Antarctic sea anemones (members of the genus Hormathia or similar) and sea squirts (from the subphylum Tunicata) clinging to the timbers of the outside of the 107-year-old shipwreck.

Related: In photos: Searching for Shackleton's Endurance shipwreck

But the star of the show was the "squat lobster" seen in some photographs scuttling past a wooden porthole of the ship, which sank in Antarctica's Weddell Sea in 1915.

Squat lobsters may look like lobsters, but they are actually more closely related to hermit crabs, according to the Monterey Bay Aquarium.

The animal could be from the genus Munidopsis, which is known to have over 200 species, Griffiths told BBC News. One species was found in 2006 on the western side of the Antarctic Peninsula, but this would be a first for the Weddell Sea on the eastern side, he said.

Endurance wreck

The wreck of the Endurance was discovered on Saturday (March 5) by searchers on board the South African polar research vessel Agulhas II.

It was famously crushed in November 1915 by sea ice and sank to the bottom of the Weddell Sea during an expedition led by polar explorer Ernest Shackleton, after becoming surrounded by ice several months earlier.

The Endurance was Shackleton's expedition ship. He'd intended to begin a crossing of the entire Antarctic continent from the south coast of the Weddell Sea.

But he and his crew had to abandon the ship after it became trapped; instead they made an extraordinary journey of survival across the ice on dog-sleds and the freezing seas by lifeboats, first to the tip of the Antarctic Peninsula and then to the sub-Antarctic island of South Georgia. Remarkably, they all survived.

The wreck was found at a depth of almost 10,000 feet (3,000 meters) beneath the Weddell Sea, which is often completely covered by sea ice.

It's impossible for any light to reach such a depth, meaning that plants that rely on photosynthesis can't live there; and so the animals on the wreck can only survive by eating other animals or feeding off the "marine snow" of dead algae, tiny animals and their waste that falls from the often-icy surface, where sunlight can penetrate for a very small distance.

Filter-feeders

Most of the animals Griffiths spotted on the wreck photos were "filter feeders" that survived by eating marine snow, he wrote on Twitter.

He also noted the photos showed starfish or sea-stars (order Brisingida) and stalked animals that were probably glass sponges (class Hexactinellida) — similar sponges have been found under Antarctica's Filchner ice shelf.

Griffiths said one of his favorite creatures on the wreck is a bright yellow sea-lily, a stalked type of crinoid.

"Sea lilies date back over 480 million years and used to be very common and diverse in all the world's oceans until the Triassic period," he said. 

Other sea creatures on the Endurance wreck may be confirmed as researchers examine more of the high-resolution imagery from the autonomous underwater vehicles that found the wreck.

Essex University marine biologist Michelle Tasylor, who like Griffiths wasn't involved in the search for the Endurance wreck, told BBC News that the fan-like structure near the ship's wheel may be a type of hydroid — effectively a colony of tiny creatures that live together.

"They are the fine, slightly stingy fur that you find covers the bottles of boats very quickly," she said.

But researchers don't expect to find on the wreck any wood-eating bacteria, fungi or shipworms, which can quickly destroy the timbers of sunken wrecks.

Portsmouth University marine zoologist Simon Cragg told BBC News that those organisms were likely to have been kept at bay by the cold waters around Antarctica — and indeed it seems that the wooden wreck is in a remarkable state of preservation.

Originally published on Live Science.

The wreck of the steam-yacht Endurance, which famously sank in 1915 during an Antarctic expedition by the polar explorer Ernest Shackleton, has been rediscovered by searchers using autonomous underwater vehicles.

The shipwreck was found at a depth of 9,869 feet (3,008 meters) beneath West Antarctica's Weddell Sea, according to the Falklands Maritime Heritage Trust (FMHT), which sponsored the search.

That's only about 4 nautical miles (7 km) south of the location fixed by the ship's captain, Frank Worsley, who used a sextant to record the position of its sinking after several months of the ship being surrounded and eventually crushed by ice.

Related: Retouched photos of Shackleton's 1914 expedition

"This is a milestone in polar history," the search expedition's director Mensun Bound said in a statement. "We are overwhelmed by our good fortune in having located and captured images of Endurance."

Shackleton recorded that the ship was crushed by masses of surrounding sea ice in its final weeks, which tipped it over, stove in several planks in the stern and caused its timbers to groan, crack, and "scream."

But the nearly-found wreck of the Endurance seems remarkably well-preserved, in spite of its trials.

"This is by far the finest wooden shipwreck I have ever seen," Bound said. "It is upright, well proud of the seabed, intact, and in a brilliant state of preservation. You can even see [the name] 'Endurance' arced across the stern."

Years of searching

The rediscovery is the culmination of years of searching for the wreck of the Endurance, which became famous partly because of the dramatic photographs of its sinking and the astonishing journey of survival that followed.

But the wreck is located only a few hundred miles from the coast of Antarctica; the region is often completely covered with sea ice, which has forced previous search efforts to turn back.

Related: In photos: Searching for Shackleton's Endurance shipwreck

A team of searchers on board the South African polar research vessel Agulhas II finally located the wreck on Saturday (March 5) — by coincidence, the hundredth anniversary of Ernest Shackleton's funeral in 1922.

"We have successfully completed the world's most difficult shipwreck search, battling constantly shifting sea-ice, blizzards, and temperatures dropping down to -18 C [minus 0.4 F]," the search expedition's leader John Shears told BBC News. "We have achieved what many people said was impossible."

Antarctic shipwreck

The wreck of the Endurance was found by a Saab Sabertooth hybrid underwater vehicle controlled by operators on the Agulhas II. The robotic vehicles can operate both on a tether or autonomously, as they did on the latest search.

After more than two weeks of searching a predefined search area based on Worsley's original sextant fixes, Agulhas II spotted the wreck, according to the FMHT.

The FMHT notes that the wreck is protected as a Historic Site and Monument under the Antarctic Treaty, and said it would not be touched or disturbed in any way while it is being surveyed from the Agulhas II.

The search expedition has been fortunate with conditions in the Weddell Sea, which can be notoriously icebound. Last month saw the lowest extent of Antarctic sea-ice recorded during the satellite era, which stretches back to the 1970s, the BBC reported.

Treacherous voyage

Shackleton used Endurance on his third of four expeditions to Antarctica. 

He had visited the frozen southern continent twice before, from 1901 to 1903 as a subordinate of the polar explorer Robert Falcon Scott — during which time he took part in the first hot-air balloon flight from Antarctica — and then from 1907 until 1909, when his team reached the estimated location of the South Magnetic Pole.

A team led by the Norwegian explorer Roald Amundsen was the first to reach the geographic South Pole on Dec. 14, 1911, a few weeks ahead of a team led by Scott, which ended in tragedy. 

Shackleton's aim in 1915 was to complete the first complete crossing of the Antarctic continent, by dog-sled from the Weddell Sea via the South Pole to Ross Island in the Ross Sea — a distance of about 1,800 miles (2,900 km).

The Endurance was meant to deliver Shackleton and his team to the southern coast of the Weddell Sea for the overland expedition. But the ship became trapped in heavy sea ice in October 1915, and the crew abandoned it and moved everything they could onto their camp on the ice floes.

After the Endurance sank, Shackleton and the other 27 members of his crew attempted to reach land by dogsled and eventually on lifeboats they had rescued from the ship.

In April 1915, they reached Elephant Island at the northern tip of the Antarctic Peninsula; Shackleton and five members of the crew then set out in one of the lifeboats through the stormy, freezing seas, for a whaling station on the sub-Antarctic island of South Georgia.

Shackleton returned to Elephant Island on a rescue ship shortly after, and — remarkably — all 28 of his crew survived the treacherous voyage.

Originally published on Live Science.

Seismic activity from an underwater volcano near Tokyo has raised two dozen "ghost ships" — sunk after one of World War II's most famous battles — from the bottom of the Pacific Ocean.

Helicopter footage from Japan's All Nippon News (ANN) captured the 24 ships washed ashore on the western side of the island of Iwo Jima, which is roughly 760 miles (1,200 kilometers) south of Tokyo, after they were pushed up, along with the seabed, by the underwater volcano Fukutoku-Okanoba.

U.S. forces sank the ships during the Battle of Iwo Jima in 1945. One of the bloodiest battles in the Pacific War, during WWII, the 36-day assault saw roughly 70,000 U.S. Marines fight around 20,000 Japanese soldiers hiding out in bunkers within the island's volcanic rocks. By the end of the battle, 20,000 marines had been wounded and nearly 7,000 killed. Nearly all of the Japanese soldiers, save for 216 captured alive, were killed in action. 

Related: Mayday! 17 mysterious shipwrecks you can see on Google Earth 

The smashed, sea-bleached wrecks are the remnants of transport vessels that were captured by the U.S. Navy and deliberately scuttled in the aftermath of the battle. As Iwo Jima had no port, the ships were sunk parallel to the shoreline to form a breakwater — shielding both weapons and troops from oncoming waves as they were unloaded onto the island, according to the US National Archives. 

Fukutoku-Okanoba has been erupting underwater since August. Besides pushing the ships, and the seabed they are resting upon, into view, the seismic activity produced by the volcano has led to the emergence of a small, crescent moon-shaped island from the sea. Formed from pumice and volcanic ash, the island is expected to vanish soon due to erosion, according to Setsuya Nakada, the director of the Japanese government's Center for Integrated Volcano Research.

Iwo Jima is part of the Bonin Islands, a chain of roughly 30 subtropical islands in the Pacific Ocean. Created by the subduction of the Pacific tectonic plate below the Philippine Sea Plate, the island chain is prone to earthquakes and volcanic eruptions, and it has been experiencing an uptick of seismic events in recent weeks, according to Japan’s Meteorological agency. For instance, on Oct. 7, a magnitude-5.9 tremor shook buildings across Tokyo and eastern Japan. And another volcanic island in the chain, Nishinoshima, has been spewing gas and lava since 2013.

Iwo Jima's Mount Suribachi is the dormant vent to a still-active volcano, and is considered by some to be among the 10 most dangerous volcanoes in the world, according to a list made by one astrophysicist. In fact, there's every indication that the current spate of seismic activity could be building toward an eruption.

"The discolored sea area has spread to surrounding areas, which indicates that the volcanic activity has not diminished yet," Nakada told the All Nippon News channel. "There is a possibility of a big eruption on Iwo Jima."

Barring another eruption of Mount Suribachi or the sinking of the seabed that the ghost ships are resting upon, the once sunken monoliths will likely remain on the island for some time to come. Iwo Jima is uninhabited and rarely visited by civilians — partly as a result of the enormous quantities of unexploded bombs and grenades left behind on the island — meaning that it is unlikely that the ships will be cut up for scrap or removed by Japanese authorities.

Originally published on Live Science.

Powerful X-rays have revealed what's eating the wreck of King Henry VIII's favorite warship, the Mary Rose. After the ship sank in a 1545 battle against the French, sulfur-producing marine bacteria spent the next few centuries munching on the wood of the submerged wreck, leaving behind residues that could turn to acid when exposed to air and harm the historic shipwreck today, researchers recently discovered. 

The Mary Rose — what was left of it — languished at the bottom of the English Channel until the ship was raised in 1982, and though conservators took steps to treat and preserve the waterlogged structures, little was known about the bacterial species inhabiting the wood and if their byproducts could jeopardize the rescued ship's preservation.

By combining X-rays with a technique that compares atoms of molecules in the ship's wood, scientists detected acid-forming nanoparticles that were byproducts of destructive bacteria. Identifying and pinpointing the location of acid-forming compounds that could erode the ship, will help conservators to protect this one-of-a-kind artifact.

Related: Sunken treasures: the curious science of 7 famous shipwrecks

This novel method "allows us not only to image and locate these nanoparticles in Mary Rose wood, but also to evaluate their structure," said study lead author Serena Cussen, head of the Department of Materials Science and Engineering at the University of Sheffield in the U.K.. 

"This is the first time zinc sulfide nanostructures — the bacterial byproducts — have been observed in Mary Rose wood," Cussen said in a statement. Previously, scientists were unable to get such a highly detailed view of potentially harmful bacteria species, she added.

When King Henry VIII ordered the construction of the Mary Rose in 1510, he was just 19 years old and had assumed the throne one year earlier. At the time, the Mary Rose was a "state-of-the-art" warship capable of carrying up to eight large guns and weighing about 600 tons (544 metric tons), according to the Mary Rose Trust in Portsmouth, U.K. The Mary Rose sailed in two wars against France before capsizing — "for reasons unknown" — during a battle against the French armada, and it sank to the ocean bottom along with a crew of about 500, according to the Trust.

Divers discovered the Mary Rose in 1971 in the Solent, a strait between Great Britain and the Isle of Wight (an island in the English Channel, and a county in England); and over the next decade, more than 500 divers and researchers helped to excavate the vessel, removing individual artifacts one at a time. Then, in 1982, a team of experts raised the ship's hull, about half of which was still intact. It was treated with polyethylene glycol (PEG), a compound for stabilizing water-saturated wood and preventing shrinkage as the wood dries, scientists wrote in a new study. 

However, even after being treated, waterlogged wood can still be vulnerable to deterioration. Plenty of sulfur-producing bacteria can still lurk in the wood, and as PEG breaks down over time, it too can generate harmful acids, according to the study.

"There are potentially several tons of sulfur-containing species, as well as PEG breakdown products, residing in the Mary Rose hull, highlighting the magnitude of this problem," the authors reported.

They sampled a 2-inch-long (5 centimeters) wood core from the Mary Rose's hull, slicing the sample into smaller pieces for analysis with X-rays and scanning electron microscopy (SEM). When the scientists compared scattering patterns in the data based on the atomic structures of compounds in the wood, they were able to detect iron sulfide-based nanostructures, which are produced by bacteria and can form harmful acids when they interact with oxygen.

"What our results have done is alert conservators to these previously unknown deposits and expand the study of degradation-inducing materials," Cussen said in the statement. "Knowing the structure of these potentially harmful species also allows us to design targeted treatments for their future removal."

The findings were published Oct. 27 in the journal Matter.

Originally published on Live Science.

The latest expedition by divers to the wreck of the Mentor, which sank just off the island of Kythera (also spelled Kithira and Kythira) in 1802, has recovered several pieces of the ship's rigging, coins, the leather sole of a shoe, a metal buckle, a token for playing cards, two chess pieces, fragments of cooking utensils and other seemingly mundane objects.

When it sank, the ship was carrying marble sculptures chipped from the badly damaged Parthenon in Athens — later known as the "Elgin Marbles or Parthenon Marbles. These spectacular sculptures — which depict Greek gods, heroes and animals — are now on display at the British Museum in London.

Related: 20 of the most mysterious shipwrecks ever

But the small objects recovered from the wreck reveal intriguing aspects of the lives of the people onboard the ship when it sank, said marine archaeologist Dimitris Kourkoumelis, of the Ephorate of Underwater Antiquities, a department of the Greek Ministry of Culture and Sports.

"The target is to understand how people were living and how was life onboard, not only for the passengers but also for the crew," Kourkoumelis told Live Science. "We've found gold coins from Utrecht in Holland, as well as from Spain, and also coins from the Ottoman Empire — so it was really a cosmopolitan group [of people] on the Mentor." 

Disputed sculptures

The Mentor was an American-built brig that belonged to the British diplomat Thomas Bruce, a Scottish nobleman titled the seventh Earl of Elgin. Elgin, as he was known, used the ship to carry antiquities to England that he'd collected while stationed in Constantinople as Britain's ambassador to the Ottoman Empire.Although the ship made it to Kythera, where its passengers and crew scrambled onto the rocks, the Mentor soon sank beneath about 65 feet (20 meters) of seawater. 

Elgin's secretary, William Hamilton, then spent almost two years on Kythera, overseeing the salvage of the sculptures by sponge divers, who were paid to recover them from the wreck without any diving equipment.

Related: 30 of the world's most valuable treasures that are still missing

The sculptures were then shipped to England, and Elgin sold them to the British Museum in 1816. 

Elgin claimed he'd paid for the sculptures and that he'd obtained a decree from the ruling Ottoman government to take them. But no evidence of the decree has ever been found, according to the British Committee for the Reunification of the Parthenon Marbles, a nongovernmental organization.

When Greece recovered its independence from the Ottomans in 1832, it began a series of projects to retrieve looted art, and the Elgin Marbles were at the top of the list. Since then, every successive Greek government has demanded that the sculptures be returned. So far, however, the British Museum has refused, although it has offered to loan them out temporarily. 

Famous shipwreck

Kourkoumelis has led diving expeditions to the wreck of the Mentor every summer since 2009, after the Greek government enacted legislation to protect the shipwreck and formally ordered state archaeologists to excavate it. 

According to Kourkoumelis, the construction of the Mentor is very different from that of similar ships built in the Mediterranean. "The American ships were built to travel in the open ocean, and so they were much stronger — it's very interesting to work on a ship like that," he said.

The wooden vessel is now rotting away after more than 200 years under the waves, and only a few more years of excavations will be possible, he said.

No more items from Elgin's collection have ever been found, but the wreck has yielded numerous small objects over the years, including gold jewelry, ancient coins and Greek pottery that probably came from the private collections of some of the passengers onboard when it sank, he said.

The most recent finds last year included two wooden chess pieces — another six pieces from the same set were found in previous years — and a metal token or coin that was probably used in a card game. 

Archaeologists plan to scientifically examine all of the items, many of which will be displayed at the Acropolis Museum in Athens, Kourkoumelis said. The museum already displays about half of the Parthenon sculptures that remain, and it has space reserved for the Elgin Marbles if they are ever returned to Greece.

"We are excavating the ship that is associated with one of the most painful episodes of the recent history of Greece," Kourkoumelis said. "I think it is very important to show that we are not only asking for things, but we are working for the protection of everything that is involved."

Originally published on Live Science.

The wreck of a German steamship sunk at the end of World War II has been found by divers, -- and the crates on board the submerged vessel could hold a prize treasure: the precious furnishings of the lost 18th century Amber Room, which German soldiers looted from a Russian royal palace.

The shipwreck was found north of the Polish seaside town of Ustka, at a depth of 290 feet (88 meters), after more than a year of searching for it on the floor of the Baltic Sea, said Tomasz Stachura, who led the discovery. Stachura is one of the founders of the Baltictech dive team. By a curious coincidence, the wrecked ship has the same name — Karlsruhe— as a WWII German warship found off Norway last month, which was sunk in 1940. Both ships were named after a city in Germany.

Related: In photos: WWII ship discovered 77 years after it sank 

The 196-foot-long (60 m) steamer SS Karlsruhe took part in the massive German evacuation of East Prussia in April 1945, dubbed Operation Hannibal by the Nazi leadership, which took place as the Soviet Red Army  advanced westward.

On April 12,  the Karlsruhe became the last German ship to leave Königsberg — now Kaliningrad in Russia; other parts of East Prussia became parts of Lithuania and Poland after the war. The steamer headed west, but it was sunk by Soviet warplanes the next day.

Some historians have long-suspected that the many crates loaded onto  the ship held what's left of the famous Amber Room, an ornately decorated chamber of a Russian palace looted by the Germans and then lost during WWII, Stachura told Live Science in an email. 

"The truth is that if the Germans were to take something valuable from Königsberg, it was the Karlsruhe that was their last option," he said. 

Amber Room

The Amber Room was, as its name suggests, filled with hand-crafted amber. Its construction began in 1701, when a German baroque sculptor and Danish amber craftsman designed it for Charlottenburg Palace, the home of Friedrich I, the first King of Prussia, according to Smithsonian Magazine. 

The room had many admirers, including Russia's Peter the Great. During a visit to Berlin in 1716, and when Prussia's king Frederick William gave Peter the panels as a gift, the Russians added enough amber, gold leaf, gemstones and mirrors to furnish an entire room — a task that took more than 10 years to complete.

When it was finished and installed in Catherine Palace at Tsarskoe Selo ("Czar's Village") on the outskirts of St. Petersburg, the chamber contained more than 6 tons (5.4 metric tons) of amber, as well as artworks and other precious objects. These treasures are estimated to be worth up to $500 million today, United Press International (UPI) reported.

But the Amber Room was captured as spoils of war in 1941 by invading German soldiers. Although the Soviets tried to hide the amber panels by covering them with wallpaper, the Germans  discovered, dismantled and transported it in pieces to Königsberg, where it was reassembled for display in the town's castle.

After the German evacuation of Königsberg in 1945, however, the treasures of the Amber Room were never seen again -– and some suspect they were secretly  transported further into Germany, possibly on the steamer Karlsruhe.

Some investigators, however, allege that the Amber Room was packed into crates that were destroyed when Soviet soldiers burned down part of the castle — an embarrassing calamity later covered up by Soviet authorities. 

Related: Photos: German WWII base discovered on Arctic island

Mystery shipwreck

To investigate the matter further, the team of Polish divers searched for the wreck of the Karlsruhe steamer by cross-referencing underwater sites reported by fishermen who had snagged their nets with the locations of attacks by Soviet warplanes described in military records, Stachura said.

The team used sonar to locate 22 wrecks that matched the dimensions of the ship, and dove to those spots. On Sept. 24 of this year, they identified the Karlsruhe from its distinctive bow on their third drive to that wreck, he said.

The ship had left Königsberg on the evening April 12 with more than 1,000 refugees and 360 tons (326 metric tons) of cargo on board; but it was hit by a Soviet warplane's torpedo dropped on the morning of April 13, and only 113 people survived.

Stachura said the wreck is relatively intact, and that they've seen military vehicles and several crates on board; but the divers can't tell whether any of the crates hold the looted remains of the lost Amber Room.

"Diving at a depth of 88 m [290 feet] is very difficult," he said. "We have focused only on the inventory, video shooting and photographic documentation."

And he can't say yet just when its mysterious cargo could be recovered: "The possible examination of the load will have to be discussed with the Maritime Office in Gdynia, Poland, and they will make the final decision," he said.

Originally published on Live Science.

Divers in Southeast Asia have located the lost wreck of what's thought to be a U.S. Navy submarine that sank in 1943 after it was attacked by Japanese aircraft. 

The submarine wreck — almost certainly that of USS Grenadier — was found in a search of the northern end of the Straits of Malacca, between the Malay peninsula and Sumatra. 

The divers cross-referenced military records of three submarines sunk in the area during World War II with the possible locations of wrecks reported by fishermen who had snagged nets on submerged obstacles, said team member Lance Horowitz, an Australian based on Thailand's southern island of Phuket.

Related: Photos: WWII shipwrecks found off NC coast

The other members of the team are Ben Reymenants, a Belgian diver based in Phuket who also helped rescue a youth soccer team from a cave in Thailand in 2018; and Frenchmen Jean Luc Rivoire and Benoit Laborie, who are both based in Singapore. 

The team spent two boat trips and several days searching the most likely areas with sonar equipment, and located a wreck in October last year at a depth of 280 feet (85 meters) — an extreme depth for diving that required a special mix of oxygen, nitrogen and helium for them to breathe, and only let them stay a few minutes.

"We didn't really have too much time," Horowitz told Live Science. "We weren't able to swim around the whole wreck … it kind of disappears off in either direction."

After five more dives since, Horowitz and his team have established the wreck as that of a military submarine with all its hatches open, sitting on the seafloor; — the latest measurements of its conning tower, hatches and hull show it must be the Grenadier. 

The team is now waiting for formal confirmation of their find from the U.S. Navy, Horowitz said.

Stricken submarine

USS Grenadier, named after a type of fish like many U.S. subs, joined the American submarine fleet in the Pacific Ocean after the Japanese attack on Pearl Harbor in December 1941.

It helped defend the island of Midway in June 1942 — one of the decisive naval battles of the Pacific during World War II — and later patrolled the coasts of Southeast Asia, according to the U.S. Naval History and Heritage Command.

On April 20, 1943, the Grenadier was closing on two Japanese cargo ships near Phuket, intending to sink them, when it was spotted by a Japanese aircraft. The submarine crash-dived to a depth of around 120 feet (36 m), but it was hit by a torpedo dropped from the aircraft, which knocked out its power and started fires onboard.

Related: Photos: WWI-era German submarine wreck discovered off Scotland coast

The stricken submarine fell to the seafloor, while its crew tried to make repairs and put out the fires; it only surfaced after dark, 13 hours later, but it was too badly damaged to move.

The sub's captain, Lt. Cmdr. John Fitzgerald, hoped an improvised sail would bring the sub close enough to shore that the crew could escape into the jungle; but it was soon spotted by Japanese ships and aircraft.

After a fierce battle with the sub's guns on the surface, Fitzgerald ordered that the Grenadier be scuttled; the crew opened all its hatches and vents, and the sub quickly sank to the bottom. Its location was lost until the dive team discovered it last year.

Prisoners of war

That wasn't the end of the story for the crew of the Grenadier, however. The Japanese ships picked up all 76 crew men and took them to a commandeered Catholic school near Penang where they were questioned, beaten and starved, according to historical accounts.

In the book "The Silent Service in World War II" (Casemate Publishers, 2012), one of the Grenadier sailors alleged their Japanese captors tortured the crew, including breaking their fingers and pricking them with bayonets, to get them to talk.

Four of the Grenadier crew died in captivity, and the rest survived until the end of the war in Japanese prison camps. The last survivor of the Grenadier died last year, Horowitz said, adding that he and his team gathered their information from the families of the crew members.

The wreck has now become a haven for sea life. "It's in an otherwise barren part of the seafloor," he said. "It is really thriving, covered with coral and giant fish."

The team hopes to make further dives on the wreck and eventually search for two other World War II submarines that sank in the area: the British subs HMS Stonehenge, which sank in 1944, possibly after hitting a mine; and HMS Porpoise, which sank in 1945, after it was bombed by a Japanese aircraft.

"We'll use similar techniques that we used to find the [Grenadier]," Horowitz said. "We might get lucky enough to find another one."

Originally published on Live Science

A sunken ship discovered near Sisal, Mexico, holds the secrets of a 19th-century tragedy.

Three years after the ship's discovery, archaeologists have confirmed its identity as an illegal slave vessel. The steamer was carrying Mayan captives to work as slaves in the brutal sugarcane fields of Cuba in 1861, months after the forced removal of the Maya from Mexico had been made illegal. The ship caught fire and sank, killing dozens of passengers and crew and an unknown number of enslaved Maya.

According to the National Institute of Anthropology and History (INAH), the sunken steamer La Unión was first discovered 2 nautical miles (3.7 kilometers) from the Yucatecan port of Sisal in 2017. At first, the identity of the wreck was a mystery; archaeologists dubbed it "Adalio" after the grandfather of the fisherman Juan Diego Esquivel, who introduced the archaeologists to the site.

Related: The 25 most mysterious archaeological finds on Earth

Shipwreck detectives

It took three years to map, analyze and identify the wreck. Archaeologists recognized that the ship's boilers and paddle wheels were a type of technology that dated to ships built between 1837 and 1860. They also found pieces of glass bottles, ceramics and brass cutlery amid the wreckage.

The next step was a historical detective mission. The researchers searched the archives of Yucatán, Baja California Sur, Cuba, Spain and Mexico to find a ship that would have been in that area and matched the description of the wreck. La Unión proved to be a match.

The steamer was owned by a Spanish company called Zangroniz Hermanos y Compañía, which began trading between Havana, Cuba, and several ports in Mexico in 1854. Officially, the ship carried paying passengers and merchandise such as tanned hides. But the ship also had a darker purpose.

Related: 17 mysterious shipwrecks you can see on Google Earth

In October 1860, La Unión was caught in Campeche, Mexico, carrying 29 Maya, the native people of Central America who were conquered by the Spanish in the 1600s. Following the conquest, the Maya and other Indigenous people were often enslaved on plantations, especially those specializing in sugarcane and coffee. The 29 Maya found in 1860 included children as young as 7.

The loss of La Unión

Slavery was abolished in Mexico in 1829. In May 1861, Mexican president Benito Juárez banned the forcible removal of Indigenous people for sale in other nations. But as the story of La Unión shows, the slave trade continued.

"Each slave was sold to middlemen for 25 pesos, and they resold them in Havana for as much as 160 pesos, for men, and 120 pesos for women," INAH archaeologist Helena Barba Meinecke said in a statement.

This human trafficking occurred against the backgdrop of the Castle War, a clash between Indigenous peoples and the upper classes of Spanish descent, who were levying heavy taxes and seizing farmland from the Indigenous population. Captured Mayan combatants were sold into slavery, often in Cuba, according to INAH. In other cases, slavers called "enganchadores" would travel to Indigenous villages and promise citizens that in Cuba, they would be given their own land. Once the villagers reached Cuba, of course, they were instead enslaved.

Historians estimate that La Unión and another steamer called México, both owned by the same company, smuggled 25 to 30 people to Cuba each month between 1855 and 1861.

On Sept. 19, 1861, La Unión's boilers exploded, setting the steamer aflame. Half of the 80 crew members and 60 paying passengers aboard died. No one knows how many Mayan captives lost their lives, as they were listed as cargo rather than passengers.

The conflagration did draw attention to the illicit human trafficking that was occurring right under the Mexican government's nose, according to INAH. After the loss of La Unión, the government increased searches at Mexican ports to stop the transport of enslaved people. 

Originally published on Live Science.

Glowing auroras shimmered in skies over the northern Atlantic Ocean on April 15, 1912 — the night the RMS Titanic sank. Now, new research hints that the geomagnetic storm behind the northern lights could have disrupted the ship's navigation and communication systems and hindered rescue efforts, fueling the disaster that killed more than 1,500 passengers. 

Eyewitnesses described aurora glows in the region as the Titanic went down, with one observer testifying that "the northern lights were very strong that night," Mila Zinkova, an independent weather researcher and photographer, reported in a new study, published online Aug. 4 in the journal Weather.

Related: In Photos: Stunning shots of the Titanic shipwreck

Auroras form from solar storms, when the sun expels high-speed streams of electrified gas that hurtle toward Earth. As the charged particles and energy collide with Earth's atmosphere, some travel down magnetic field lines to interact with atmospheric gases, glowing green, red, purple and blue, NASA says. These charged particles can also interfere with electrical and magnetic signals, causing surges and oscillations, according to NASA.

A solar storm (also called a geomagnetic storm) powerful enough to produce an aurora may also have affected compasses and wireless communication on the Titanic, and on nearby ships trying to come to her aid. Even a small disruption might have been enough to doom the vessel, Zinkova said in the study.

And the northern lights were highly visible when the Titanic sank. James Bisset, second officer of the RMS Carpathia (the ship that would rescue Titanic survivors) wrote in his log on the night of April 14, 1912: "There was no moon, but the Aurora Borealis glimmered like moonbeams shooting up from the northern horizon." In an entry made five hours later, Bisset noted that he could still see "greenish beams" of the aurora as the Carpathia neared the Titanic's lifeboats, Zinkova reported.

Survivors also described spotting the northern lights from their lifeboats at around 3 a.m. local time. The glow "arched fanwise across the northern sky, with faint streamers reaching towards the Pole-star," Titanic survivor Lawrence Beesley wrote.

At the same time that the solar storm's charged particles were generating a pretty light show, they could also have been tugging at the Titanic's compass. A deviation of only 0.5 degrees would have been enough to steer the ship away from safety and place it on its fatal collision course toward an iceberg, Zinkova said in the study. 

"This apparently insignificant error could have made the difference between colliding with the iceberg and avoiding it," she wrote. 

"Freaky" signals

Radio signals that night were also "freaky," operators on the ocean liner RMS Baltic reported (the Baltic was one of the ships that responded to the Titanic's distress call, but the RMS Carpathia got there first, according to the Armstrong Browning Library at Baylor University in Waco, Texas). SOS signals sent by the Titanic to nearby ships went unheard, and responses to the Titanic were never received, according to Zinkova. 

Related: Infographic: Why and how the Titanic sank

"The official report of the Titanic sinking suggested amateur radio enthusiasts had caused interference, by jamming the airwaves, and so prevented the accurate dissemination of emergency signals to other ships in the vicinity," she wrote. 

"However, at the time they had incomplete knowledge of the influence that geomagnetic storms may have on the ionosphere and disruption to communication. It is proposed here that the ongoing moderate to strong geomagnetic storm near the aurora had a negative impact upon the receipt of accurate SOS signals by nearby vessels, as well as interference from amateur radio operators." 

If geomagnetic disruption from a solar storm did take place, "it could have affected all aspects of the tragedy," including the navigation errors that caused the iceberg collision, and the failed SOS communications that delayed the arrival of rescue ships, Zinkova wrote. 

Though the Titanic sank more than 100 years ago, the tale of that fateful voyage and its tragic conclusion continues to intrigue and fascinate. Objects recovered from that fateful day command hefty price tags at auction, such as a first-class lunch menu from April 14 that sold for $88,000 in 2015, and the battery-illuminated "flashlight cane" of a passenger and survivor that sold for $62,500 in 2019.

But while the ship's fame is undimmed, the wreck itself is rapidly disintegrating. When a team of explorers visited the Titanic in August of 2019, the first divers to do so in 14 years, they found that part of the ship's starboard side — where many of the state rooms were located — had been eroded by powerful ocean currents, metal-destroying microbes and corrosive salt, Live Science previously reported.

Originally published on Live Science.

Divers from Finland have made an unexpected discovery while exploring the depths of the Baltic Sea, finding an incredibly well-preserved shipwreck dating back almost 400 years.

Volunteer divers from the nonprofit Badewanne team more often come across wrecked 20th-century relics sunk during the sea battles of World War I and WWII, so uncovering what appears to be a largely undamaged Dutch merchant vessel from the 17th century was a huge surprise.

The ship, an example of a Dutch 'fluit' (or fluyt), was found near the mouth of the Gulf of Finland, in the easternmost waters of the Baltic.

At a depth of about 85 meter (roughly 280 ft), the Badewanne diving team discovered this Dutch time capsule lying on the seabed, almost completely preserved and intact.

Showing only minor damage sustained from subsequent pelagic trawling with fishing nets, the vessel is otherwise frozen in a kind of 17th-century stasis, the team says, thanks to the properties of the water in this part of the sea — where a combination of low levels of salinity, temperature, and light can enable sunk wrecks to survive virtually unchanged for hundreds of years.

In warmer waters, wood-boring organisms flourish, and can do untold damage to relics such as this, but here, the chemistry of the Baltic — and the unknown nature of the fluit's sinking — have left us with a remarkable relic for further investigation.

Even the holds of the ship are full, the divers say, still carrying its stock of provisions and wares from when Dutch cargo vessels largely dominated seaborne trade in this part of the world, thanks in part to the pioneering advancements demonstrated by the fluit itself.

These ships, which in their first iterations emerged in the 16th century, sacrificed everything for their all-important cargo. Unlike other boats of the time that were designed to switch between serving as cargo ships and war vessels, the three-masted fluit bore a cost-effective and capacious design fully intended to maximize cargo capacity.

Because of this, it could carry as much as twice the cargo of rival vessels, and advanced rigging systems ensured its deft sailing capabilities could be controlled by small crews, which also made the fluit a more profitable ship to operate.

Despite the design's success and popularity between the 16th and 18th century, relatively few fluits survive to this day. Further investigation of this particular find could reveal interesting facts about these historical treasures.

"The wreck reveals many of the characteristics of the fluit but also some unique features, not least the construction of the stern," says maritime archaeologist Niklas Eriksson from the University of Stockholm in Sweden, who will work with Finnish authorities and others to study the discovery.

"It might be that this is an early example of the design. The wreck thus offers a unique opportunity to investigate the development of a ship type that sailed all over the world and became the tool that laid the foundation for early modern globalization."

This article was originally published by ScienceAlert. Read the original article here.