The Mediterranean Ocean has dried out more than 40 times however, the last time was 5 million years ago. There is salt two miles thick on the bottom that was formed by drying in sunlight
Now, it is my opinion that the Med was blocked at Gilbralter during the Ice Age and the water level in the Med was greatly reduced, that would have allowed Neanderthal to walk across.
This theory would have allowed for large areas of the Mediterranean to have been dry and also contain a larger number of islands during the long period of the Ice Age.
If Atlantis was in this area, the flood waters, earthquakes, volcanos and tsunamis at the end of the Ice Age would have wrecked it and sent it below the inflowing water. The timing would be about right and the flooding into the Med would have columinated with the (Now documented) Black Sea flood.
Thanks for the info!