The island is about 781 km2 (300 mi2), with a population density of 55 people per km2 (140/mi2). The town of Argostoli has one-third of the island’s inhabitants. Lixouri is the second major settlement, and the two towns together account for almost two-thirds of the prefecture’s population.
Important natural features include Melissani lake, the Drogarati caves, and the Koutavos lagoon in Argostoli.
The island’s highest mountain is MountAinos (Enos) with an elevation of 1628 m