Kefalonia island is the largest island in the Ionian Sea, with an area of 688,8 square kilometres and the sixth in size of all the Greek islands. It has a population of 27.000 inhabitants. It lies opposite the Golf of Patras between Lefkada and Zakinthos islands. It is made up of four peninsulas Paliki, Erissos, Livathos and Atros. The biggest part of the island is mountainous, the higher of which is the mountain of Aenos up to 1628m, which is covered with fir trees of a unique variety that only grow in Kefalonia with whitish branches and sharp needles. The climate of Kefalonia island is temperate and it is sunny for the most of the year. The economy is based mainly on its agricultural production and on fishing. Kefalonia's capital is Argostoli that is the largest town of the island with a population of 7.500 inhabitants. According to Apollodorus of Athens, Kefalonia is believed to have taken its name from the handsome hero Cephalus, son of the God Hermes and the nymph Herse. Kefalonia Island is an island with many geological phenomena and treasures, such as caves and underground salt lakes, like the impressive cave of Drogarati with Stalactites and Stalagmites, that experts have estimated that to be about 150 million years old.