From the Herald Sun:
ARCHAELOLOGISTS have discovered a mysterious, ancient monumental stone structure in the waters of the Sea of Galilee.
The giant structure is cone-shaped, made of "unhewn basalt cobbles and boulders," and weighs around 54,400 tonnes, researchers wrote in the International Journal of Nautical Archaeology.
The mysterious rock pile is 10 metres high and 70 metres in diameter - about twice the diameter of Stonehenge. The basalt boulders weigh a total of about 60,000 tons.
Researchers believe the structure is a giant cairn, or rock pile that is often used to mark burials.
But its age and purpose are are not yet certain.
"The shape and composition of the submerged structure does not resemble any natural feature. We therefore conclude that it is a man-made and might be termed a cairn," researchers wrote.
They speculated it was either built under water to attract fish, or was built on dry land that has since been covered by rising sea levels.
... One of the researchers, Ben-Gurion University’s Israel Antiquity Authority Yitzhak Paz said the structure could be 4000 years old, similar to other ancient structures found nearby.
"The more logical possibility is that it belongs to the third millennium B.C., because there are other megalithic phenomena [from that time] that are found close by," Mr Paz told LiveScience.
The ancient Khirbet Beteiha, which is made up of three concentric stone circles and dates to the Bronze Age, is 30 km north east of the underwater discovery.
The Sea of Galilee find is also just north of the site of ancient city Khirbet Kerak, which was one of Israel’s largest and most heavily guarded cities in third millennium BC, researchers said.Photos and diagrams at the link.