Tanzania, East African country situated just south of the Equator. Tanzania was formed as a sovereign state in 1964 through the union of the theretofore separate states of Tanganyika and Zanzibar. Mainland Tanganyika covers more than 99 percent of the combined territories’ total area. Mafia Island is administered from the mainland, while Zanzibar and Pemba islands have a separate government administration. Dodoma, since 1974 the designated official capital of Tanzania, is centrally located on the mainland. Dar es Salaam is the largest city and port in the country.
The Tanzania mainland is bounded by Uganda, Lake Victoria, and Kenya to the north, by the Indian Ocean to the east, by Mozambique, Lake Nyasa, Malawi, and Zambia to the south and southwest, and by Lake Tanganyika, Burundi, and Rwanda to the west.
The East African Rift System runs in two north-south-trending branches through mainland Tanzania, leaving many narrow, deep depressions that are often filled by lakes. One branch, the Western Rift Valley, runs along the western frontier and is marked by Lakes Tanganyika and Rukwa, while the other branch, the Eastern (or Great) Rift Valley, extends through central Tanzania from the Kenyan border in the region of Lakes Eyasi, Manyara, and Natron south to Lake Nyasa at the border with Mozambique. The central plateau, covering more than a third of the country, lies between the two branches.