If you stood here 5.4 million years ago, you wouldn't have seen a beach but you would have looked into a deep basin 2.7 kilometer below you. The Med was nowhere to be seen, only in the deepest parts below 2700 meter below the current sea level. You would have seen a vast basin, glittering with salt crystals and dappled with lakes of hypersaline water. Tectonic movements had closed the Strait of Gibraltar. You would have seen the height of the Messinian Salinity Crisis. The cut off Mediterranean Sea was evaporating in this hot and dry climate in about 1000 years. The remains of this can still be seen today at the bottom of many parts in the Mediterranean Sea. There you can still find a thick crust of salt and gypsum.
Source: Daniel Cossins