 Since the last ice age sea level has risen as much as .Therefore, a great deal of the record of human activity throughout the Ice Age is now to be found under water.The flooding of the area now known as the Black Sea (when a land bridge, where the Bosporus is now, collapsed under the pressure of rising water in the Mediterranean Sea) submerged a great deal of human activity that had been gathered round what had been an enormous, fresh-water lake.