Archaeologists report the discovery of a conical structure measuring c.70 m in diameter at a depth of -218.5–-219.5 m.
in the Sea of Galilee (also known as Lake of Tiberias), located in northeast Israel, near the Golan Heights, in the
Jordan Rift Valley.
This ancient, shallow sub-bottom structure (up to 13 m deep) resembles a burial marker but archaeologists are not
certain of its true purpose.
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.
An underwater photo shows that the monumental structure is made of basalt boulders. Fish (marked with
arrow) is about 10 cm. (Shmuel Marco
The south-western part of the Sea of Galilee was surveyed in the summer of 2003, when the lake level was
210.7 m bmsl (below mean sea level) and it was for the first time the structure was discovered.
Click on image to enlarge
The circular structure was first detected in a sonar survey of part of the sea in the summer of 2003. Photo Credits: Shmuel Marco
At 230 feet (70 meter) in diameter, the edifice is twice the diameter of Stonehenge, where the tallest
stones do not reach the monument's 32-foot (10 meter) height. Many basalt boulders up to one meter in length
were used to create structure, which researchers are calling a cairn.
Location maps: a) The Sea of Galilee is a fault-bounded basin (faults shown with solid white lines).
The River Jordan (J, dotted line), the main water supplier to the lake, enters at the north and exits southward. Shaded
topography from Hall (1994). (Shmuel Marco); b) The lake bathymetric map based on multi beam survey (after Sade et al., 2008)
with the location of the monumental structure. Credits: Shmuel Marco
According to researchers, the unknown structure does not resemble any natural feature. Most probably it's
a man-made creation without distinguishable walls, divisions or construction patterns - probably an ancient cairn.
Archaeologists estimate that the structure is about 4,000 years old, which is similar to the age of other
nearby ancient structures.
"The only period in this region for which megalithic structures can be connected to settlement sites is the
Early Bronze Age, between the late 4th and the late 3rd millennia BCE," researchers said in the study.
To date, no underwater excavation of the structure has been carried out.
The Sea of Galilee is the largest freshwater lake in Israel, and at nearly 700 feet (200 meters) below sea
level, it Earth's lowest known freshwater lake.