Mysterious rock pile structure found beneath Sea of Galilee off Israeli coast

ARCHAELOLOGISTS have discovered a mysterious, ancient monumental stone structure in the waters of the Sea of Galilee.

Sea of Galilee Israel

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.

Galilee structure

Cairns exist around the world, marking ancient burial sites.

The structure was first spotted during a sonar scan of the Sea of Galilee in 2003, prompting researchers to don scuba gear for a closer look. The structure is made up of large boulders around 1-metre long. There appear to be no walls, divisions or construction pattern.

The "effort invested in such an enterprise is indicative of a complex, well-organised society, with planning skills and economic ability," researchers wrote in their paper.

"Close inspection by scuba diving revealed that the structure is made of basalt boulders up to 1 meter long with no apparent construction pattern," the researchers write in their journal article.

"The boulders have natural faces with no signs of cutting or chiselling. Similarly, we did not find any sign of arrangement or walls that delineate this structure."

Galilee

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.

Paz said a new expedition to examine the site was being organised.

The search will focus on finding artifacts and organic material in order to accurately date the site.

Excavation was also a possibility, he said: "We will try to do it in the near future, I hope, but it depends on a lot of factors."

Cairn