Greece, located in Southern Europe, is divided in thirteen regions and subdivided in 325 municipalities in an area of 131,940 km² with approximately of 11 millions inhabitants. The climate in Greece is Mediterranean, the most part of Greece is mountainous and the highest mountain, is the mount Olympus with an altitude of 2,919m. Greece is surrounded by the Ionian and the Aegean Sea, which are part of the Mediterranean. It has many rivers and lakes, the longest river is the Haliacmon, 322 km, and the largest lake is the Trichonida, 98,6 km². Greece attracts millions of visitors every year, with high quality accommodation services, rightfully holds the highest positions in the world ranking of tourism.