The structure was first detected in the summer of 2003 during a sonar survey of the southwest portion of the sea. Divers have since been down to investigate, they write in the latest issue of the International Journal of Nautical Archaeology.
The shape and composition of the submerged structure does not resemble any natural feature. The investigators therefore conclude that it is man-made and might be termed a cairn, rocks piled on top of each other.
Close inspection by scuba diving revealed that the structure is made of basalt boulders up to 1 m long with no apparent construction pattern. The boulders have natural faces with no signs of cutting or chiselling. Similarly, the scientists did not find any sign of arrangement or walls that delineate this structure.
It was probably was built on land, only later to be covered by the Sea of Galilee as the water level rose.
Researcher Yitzhak Paz, of the Israel Antiquities Authority and Ben-Gurion University, believes it could date back more than 4,000 years. Paz said that he hopes soon that an underwater archaeological expedition will set out to excavate the structure. They can search for artifacts and try to determine its date with certainty.