The Republic of Botswana (Tswana: Lefatshe la Botswana), is a landlocked nation in Southern Africa. Citizens of Botswana are Batswana (singular: Motswana), regardless of ethnicity. Formerly the British protectorate of Bechuanaland, Botswana adopted its new name after becoming independent within the Commonwealth on 30 September 1966. It is bordered by South Africa to the south and southeast, Namibia to the west, Zambia to the north, and Zimbabwe to the northeast. The economy, closely tied to South Africa's, is dominated by mining (especially diamonds), tourism, and cattle. Botswana is predominantly flat, tending toward gently rolling tableland. The Kalahari Desert is located in the southwest of the country. The Limpopo River Basin is the major landform of all of southern Africa, including Botswana. At 231,788 mi² (600,370 km²), Botswana is the world's 45th-largest country (after Ukraine). Botswana is dominated by the Kalahari Desert, which covers up to 70% of the land surface of the country. The Okavango Delta, the world's largest inland delta, is in the northwest. The Makgadikgadi Pan, a large salt pan lies in the north. Botswana has diverse areas of wildlife habitat, including the Okavango Delta, the Kalahari Desert, grasslands and savannas, the latter where Blue Wildebeest and many antelopes as well as other mammals and birds are found. Northern Botswana has one of the few remaining large populations of the endangered African Wild Dog.