that’s long ago...
There are Stone Age monuments similar to Stonehenge on the bottom of the Mediterranean Sea. The flood much more probably related to the collapse of the dam at the Pillars of Gibraltar. The Mediterranean was at one point a deep valley, not a sea. As sea levels rose following the ice age, the waters from the ocean broke through the entry and flooded everything, including the villages in the valley. FOr people’s of that time, that would have been “the whole world”,