Namib Desert, an arid coastal region in Namibia (South-West Africa). It extends about 1,000 miles (1,600 km) from Angola in the north to South Africa in the south. It is as much as 80 miles (130 km) wide and lies between a high inland plateau and the Atlantic Ocean. Although the desert is primarily rocky, there are vast sand dunes in the central portion. The weather is generally cool because of westerly winds moving inland from cold offshore water; morning fog is common. Annual rainfall is less than 1 inch (25 mm). Two rivers, the Orange and the Kunene, cross the desert on its extreme northern and southern edges. Diamonds are mined in the alluvial sands along the coast, while commercial fishing is important offshore. Except for a few mining towns and ports, the area is virtually uninhabited.