A submerged man-made monolith 12 meters (40 feet) in length has been discovered in a shallow bank of the Sicilian Channel between Tunisia and Sicily that's believed to date back some 10,000 years.
Weighing approximately 15 tons (30,000 pounds), the large structure was found 40 meters (130 feet) below the surface in an area that thousands of years ago wasn’t entirely submerged by the sea. Such a structure suggests not only human activity on the Pantelleria Vecchia Bank, but organized and skilled cooperation.
Sea levels have changed dramatically in the 10,000 years since the creation of the monoliths. Lodolo et al. 2015.
Found by a group of researchers surveying the area, extensive analysis of the monolith suggests that the structure, a piece of limestone, was cut and moved as a single piece of rock – despite now lying on the seabed in two pieces.
The Pantelleria Vecchia Bank wasn’t swallowed by the sea until roughly 9,350 years ago. It is thought that the rising tide forced the Stone Age residents to move camp and abandon their creation to the sea.
The huge structure lying on the seabed. Imaging shows the rock now sitting in two pieces, but analysis of the stone shows it was originally in one large piece. It also features three regular holes of similar diameter, which concurs with the theory the rock is man-made. Lodolo et al. 2015.
Researchers are currently unsure of the monolith's purpose and meaning, but the find does provide exciting evidence of significant Mesolithic human activity in the region.