The Realmonte Salt Mine in Sicily

These salt deposits were formed during the “Messinian Salinity Crisis”, a geological event during which the Mediterranean Sea was cut off from the Atlantic Ocean and dried up (or mostly dried up), creating massive deposits of previously dissolved salts. This occurred at the end of the Messinian age of the Miocene epoch, from 5.96 to 5.33 million years ago, ending when the Atlantic again flowed into the basin.

Location: Sicily, Italy

Photos © Giuseppe Fallica/500px