westward extension of the Kalahari (desert) in Namibia and extreme northwestern Botswana, locally called the omaheke (sandveld). It has an area of about 32,000 square miles (83,000 square km), lies east of the town of Grootfontein, and is bordered on the north and south by two intermittent shallow watercourses (omurambas), the Kaudom and the Epukiro, both of which drain generally eastward. On the west the Kaukauveld merges into the hardveld (rocky plain) of the Central Highland, and on the east it borders the Okavango Swamp. The Kaukauveld's sandy surface is generally flat, though occasionally the sand is swept by winds into 300-foot- (90-metre-) high dunes. Rainfall in most of the region is scanty and irregular and allows only random patches of dry grass, interspersed with bush and acacia scrub, to develop. In the north, rainfall is greater, and here baobab, fan palm, and the mopane (turpentine tree) are found. The Kaukauveld is inhabited chiefly by groups of San (Bushmen), some of whom are wandering hunters and gatherers, although most have now taken to herding cattle and goats at remote ranches. The settlement of Tsumkwe in Namibia was established to teach the San the principles of agriculture and animal husbandry.