At the junction of the Acheron and its tributary Kokytos flourished in the 5th and 6th centuries. BC Efyra the ancient city, which was known by the necromancy of building of the 5th century. B.C. Visitors flocked from all over the known world in this unique oracle, where they could stay after an initiation process and to communicate with the dead. Today, the remains of distinguished rooms, corridors, the central underground chamber, pots etc..