The monolith discovery, published in the Journal of Archaeologist Science, was made in water 131 feet deep on what researchers believe is a sunken island in a channel off the coast of Sicily. Archaeologists said they believe the monolith was made by man about 10,000 years ago, according to Discovery News.

"There are no reasonable known natural processes that may produce these elements," said Zvi Ben-Avraham, of Tel Aviv University, and Emanuele Lodolo, of the National Institute of Oceanography and Experimental Geophysics in Trieste, Italy, writing in the Journal of Archaeological Science.

Australia's News.com said the large monolith appeared to be 12 meters long and carved out of limestone. The huge stone was split in two and resting on its side on the bottom of the basin.

"The discovery of the submerged site in the Sicilian Channel may significantly expand our knowledge of the earliest civilizations in the Mediterranean basin and our views on technological innovation and development achieved by the Mesolithic inhabitants," said the researchers.