The oldest known shipwreck in the Indian Ocean has been sitting on the seafloor off the southern coast of Sri Lanka for some 2,000 years. In just a couple of weeks, scuba-diving archaeologists will embark on a months-long excavation at the site, looking for clues about trade between Rome and Asia during antiquity.
The wreck lies 110 feet (33 meters) below the ocean's surface, just off the fishing village of Godavaya, where German archaeologists in the 1990s found a harbor that was an important port along the maritime Silk Road during the second century A.D.
The sunken ship, discovered only a decade ago, doesn't look like your stereotypical skeletal hull. Instead, what archaeologists are dealing with is a concreted mound of corroded metal bars and a scattering of other ancient cargo, including glass ingots and pottery, that have tumbled around on the seafloor for hundreds of years amid strong currents and perhaps even the occasional tsunami. [See Haunting Images of Shipwrecks Across the Globe]
"Everything's pretty broken," said Deborah Carlson, president of the Institute of Nautical Archaeology at Texas A&M University, who is leading the expedition to the Godavaya wreck with colleagues from the United States, Sri Lanka and France. However jumbled it is, the wreck could fill a gap in the existing evidence for the trade that brought metals and exotic commodities like silk from Asia to the Roman world.
Scholars believe trade between the East and West intensified after Rome annexed Egypt in the first century B.C., gaining access to the Red Sea, a gateway to the Indian Ocean. Trade routes are documented in literary and historical sources, Carlson noted, such as the "Periplus of the Red Sea," a Greek-language manual from the first century A.D. that tells sailors departing from the Mediterranean and Red Seas where to go in the Indian Ocean and what to take, sell and buy.
"We just don't have the ships that were actually part of that trade," Carlson told Live Science in a phone interview.
Carlson said they likely won't find a "smoking gun" that definitively proves the doomed ship was headed for Rome. (Similarly, the archaeologists likely won't be able to tell how the ship met its demise, though Carlson — who described the "ungodly currents" that stymied many of the team's diving attempts last year — suspects the rough seas may have played a role.) But discoveries at the sunken ship might at least help illustrate that Sri Lanka was a "linchpin" in this trade, as so many of the goods that passed through the island reached the Mediterranean, Carlson said. [In Photos: Diving for Famed Roman Shipwreck]
What's down there?
The first traces of the Godavaya wreck were discovered in 2003 when local fisherman dove down to the site and came up with ancient artifacts, including a grinding stone shaped like a small bench or footed table. Similar stones have been found at relic-rich Buddhist monuments known as stupas, Carlson said.
Carlson first saw the wreck for herself in 2010. She and her colleagues partially documented the wreck during three subsequent exploratory campaigns, between 2011 and 2013. Most of the objects found around the sunken ship so far look like local commodities, many of them in their raw form. There are more Buddhist-looking grinding stones; iron and copper ingots (or what's left of them after corrosion); and blue-green and black glass ingots that originated along the Tamil coast of south India and perhaps would have been melted down to create vessels or beads.
To determine the age of the wreck, Carlson and colleagues took three samples of delicate wood embedded in the mound and sent them to two separate labs for testing. The timber fragments, which are probably remnants of the ancient ship, date back to at least the first century B.C. or first century A.D.
"I was quite skeptical when I first saw this wreck in 2010. I thought there's no way this thing is ancient," Carlson said. "But we took these wood samples and I was kind of floored when we got the results back."
The mound covers an area of about 20 by 20 feet (6 by 6 meters), though the team hasn't been able to establish exactly where the shipwreck begins and ends during their short explorations of the site. This year, they'll have more time to investigate; weather permitting, the team expects to start diving in mid-February and continue working through May.
Besides determining a solid outline for the wreck, Carlson hopes she and her colleagues will be able to secure a chunk of the underwater mound, raise it to the surface and sift through its contents in a pool, looking for coins, personal possessions and whatever else might be locked in the sediment. From closed ceramic jars, the team might even be able to recover ancient botanical materials, such as pollen, which could even indicate what time of year the vessel was at sea.
The project has received funding from the National Endowment for the Humanities. In addition to colleagues from the Institute of Nautical Archaeology, Carlson is collaborating with researchers at the French Centre National de la Recherche Scientifique, the University of California, Berkeley, and the Sri Lankan Department of Archaeology.