Kalahari (käˌlähäˈrē) [key], arid plateau region, c.100,000 sq mi (259,000 sq km), in Botswana, Namibia, and South Africa. The Kalahari, covered largely by reddish sand, lies between the Orange and Zambezi rivers and is studded with dry lake beds. Yearly rainfall varies from 5 in. (12.7 cm) in the southwest, where there are active sand dunes, to 20 in. (50.8 cm) in the northeast. Grass grows throughout the Kalahari in the rainy season, and some parts also support low thorn scrub and forest. Grazing and a little agriculture are possible in certain areas. Many game animals live in the Kalahari. Its human inhabitants are mainly San, who are nomadic hunters, and Khoikhoi, who are hunters and farmers; Tswana and Herero herders have moved into the area. The Kalahari has become a popular tourist destination; it is the site of the Kgalagadi Transfrontier Park khälˌəkhädˈē, c.14,000 sq mi (36,250 sq km), in SW Botswana and Northern Cape, South Africa. One of Africa's largest game reserves, it is a sanctuary for the animals and birds of the Kalahari. The park combines South Africa's Kalahari Gemsbok National Park khĕmzˈbôk (est. 1931) and Botswana's Gemsbok National Park (est. 1938).