At a news conference Sunday, researcher Robert Samast said he has discovered a mound with man-made structures on it some one-and-a-half kilometers below sea-level, 80 kilometers off the coast of Cyprus. Mr. Samast says sonar images reveal a 3-kilometer-long wall, a walled hill summit, and deep trenches.

He concedes he cannot yet provide tangible proof in the form of artifacts, but describes the evidence so far as "irrefutable".

There have been competing theories on where or whether Atlantis existed. Some historians speculate it could have been destroyed by flooding in the Mediterranean some 10,000 years ago.

In Greek mythology, Atlantis was a wealthy, powerful nation that became so corrupt that Zeus, the supreme ruler of all Greek gods, destroyed it.