Melissani cave, discovered in 1951, is located on the island of Kefalonia, in Karavomylos, near Sami. The roof of the cave has collapsed, offering dramatic light around noon, the best time to take the short tour around the cave in the small boats.
The groundwater of Melissani cave outflows at the "Fridi" beach. This brackish water is part of a famous hydrogeological phenomena : seawater is sucked in the west part of the island of Kefalonia, near Argotoli, and expelled in the bay of Sami. In Argostoli, the seawater flows into sinkholes, named katavothres, where water mill turns.