The Sea of Galilee
A giant "monumental" stone structure, dating to 4,000 years ago and discovered beneath the waters of the Sea of Galilee in Israel, has archaeologists puzzled as to its purpose and even how long ago it was built.
Here, the Sea of Galilee near the old city of Tiberias. The newly discovered structure is located just to the south. [Read full story
The circular structure was first detected in a sonar survey of part of the sea in the summer of 2003.
Compressed High Intensity Radar Pulse (CHIRP) provided the researchers with more information on the structure. It indiciated that its "western face is somewhat steeper than the eastern part."
Scuba divers investigated the structure revealing that it is made of basalt boulders up to 3.2 feet (1 meter) long. The rocks are piled on top of each forming what appears to be a cairn. In this image an arrow points to a 4 inch (10 cm) fish beside the structure.
Putting it together
Putting all the data together researchers found that the structure is cone shaped, about 230 feet (70 meters) in diameter and nearly 32 feet (10 meters) tall. It weighs an estimated 60,000 tons.
Close to ancient locations
They also found that it is located about 1600 feet (500 meters) off the southwest coast of the sea. Several prehistoric sites are located nearby as is the ancient city of Bet Yerah which thrived more than 4,000 years ago.
To put the structure's weight into perspective consider this - at 60,000 tons it is heavier than most modern day warships. In fact it weighs about the same as this ship, the now retired battleship USS New Jersey.
To put the structure's 230 feet (70 meters) diameter in perspective consider this. The outer circle of Stonehenge (whose central layout is shown here) has a diameter of only about half that. Also the tallest stones of Stonehenge do not reach as high as the Sea of Galilee structure.
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Owen Jarus is a regular contributor to Live Science who writes about archaeology and humans' past. He has also written for The Independent (UK), The Canadian Press (CP) and The Associated Press (AP), among others. Owen has a bachelor of arts degree from the University of Toronto and a journalism degree from Ryerson University.