The United Republic of Tanzania consists of the fairy-tale island group of Zanzibar and mainland Tanganyika with it's 1000 km long coast line and bordered in the west by the great lakes of Lake Victoria, Lake Tanganyika (one of the deepest lakes in the world) and Lake Nyasa. In the north there is Africa's highest mountain, Kilimanjaro, which peaks at 5 986 metres. In total, Tanzania covers 943 000 sq km and, of this, 59 000 sq km is lakes. The mainland consists of a central plateau between 900 metres to 1 800 metres though which where the Great Rift Valley cuts it path. A number of large rivers run towards the great lakes and the Indian Ocean. Along the coast is a low lying strip of land which stretches between 15 km to 65 km inland. There are also several mountain ranges and many volcanos. The tropical climate varies along the coast with temperatures ranging from 25C to 28C, but always with a comfortable sea breeze. On the high plateau in the north and north-west the temperature is between 20C to 27C and, in the mountain areas, the temperature can drop to 15C. There are two rainy seasons in Tanzania, the short rains from November to January and the long rains from end March to end May. In the mountains it could rain up to 2000mm in the centre of the country and, along the coast, it varies between 1000mm to 1900mm per year.