Katavothres is a natural phenomenon of “sink holes” situated just outside Argostoli on the coast road to Lassi around the Fanari Peninsula.

The area has recently been revamped and there is now an attractive bar along with a watermill. The “sink holes” display an unusual geological phenomenon; seawater pours through craters in the rocks near the shoreline and disappears underground. During the severe 1953 earthquakes, there was no change to the flow of the sea at the “sink holes”. In 1963 Austrian geologists carried out some systematic research which involved pouring dye into one of the sink holes, which eventually came out into the Melissani Lake and the sea at the village of Karavomilos, some 14 days later. These same researchers followed the trail of the water and discovered that it moves in a north westerly direction underground crossing the island and, on its way, mixes with rainwater from the water table. In this way it gathers speed, re-emerging at the other side of the island.