Very close to the city center, in Perama, is located one of themost rare caves in the entirety of the world, the Perama Cave. It has an expansion of 14.800m, and is one of the largest land caves in the Balkans. The length of the route is 1.700 meters, but the distance that visitors can travel is 1.100 meters. It belongs to the Karst limestone caves and consists of many chambers and corridors that are connected to each other and are decorated with stalactites, columns and stalagmites. We stumble across nineteen species of stalactites and stalagmites, while in the other caves there are up to six species.

The cave of Perama was discovered by accident in 1940 during the Second World war, as the inhabitants were trying to find shelter from the bombings. After the end of the war, Konstantinos Kasvikis, a gymnast and amateur speleologist, was in Perama and with the help of his team they took photos that were then published in the local and Athenian press. From the event, Ioannis and Anna Petrocheilou who visited Perama and began systematic exploration and mapping of the cave in order to be used for tourism. The tour of the cave is done in small groups with a guide helping and informing everyone about the cave.