One of the oldest monuments of the island, Aspri Petra Cave (which is around 100-140 million years old) is located at an altitude of 257 m on Zini Mountain in Kefalos, on to southwestern part of the island.
It was discovered by Alessandro Della Seta, Director of the Italian Archaeological School of Athens and archaeologist Doro Levi in 1922. According to finding, the compact and dry layers spread out in the cave allowed it to be used for habitation and after some time, it was used as a place of worship.
The excavations brought to light findings dating from the prehistoric to the Roman period, such as human bones, many vases with various designs and sizes and some weapons were found, consisting of sharp blades and obsidian stones. The food remains discovered indicate that the inhabitants were engaged in herding animals.