Now two distinguished geophysicists have discovered a catastrophic event that changed history, a gigantic flood 7,600 years ago in what is today the Black Sea. Using sound waves and coring devices to probe the sea floor, William Ryan and Walter Pitman revealed clear evidence that this inland body of water had once been a vast freshwater lake lying hundreds of feet below the level of the world's rising oceans. Sophisticated dating techniques confirmed that 7,600 years ago the mounting seas had burst through the narrow Bosporus valley, and the salt water of the Mediterranean had poured into the lake with unimaginable force, racing over beaches and up rivers, destroying or chasing all life before it. The rim of the lake, which had served as an oasis, a Garden of Eden for farms and villages in a vast region of semi-desert, became a sea of death. The people fled, dispersing their languages, genes, and memories.