Charkadio Cave is located in the center of the island about 2km south of Megalo Chorio in Tilos. Archeologists here have discovered invaluable fossils from the Paleolithic times as well as hunting tools and pieces of pottery.  More specifically, a pygmy elephant was found on site. Scientists believe that these dwarf elephants were living on the island 45,000 years ago and that they disappeared about 4,000 years ago.