The Bié Plateau, which forms the central region of the territory, has an average altitude of 6,000 ft (1,830 m). Rising abruptly from the coastal lowland, the plateau slopes gently eastward toward the Congo and Zambezi basins and forms one of Africa's major watersheds. The uneven topography of the plateau has resulted in the formation of numerous rapids and waterfalls, which are used for the production of hydroelectric power. The territory's principal rivers are the Cuanza and the Cunene. Rainfall in the south and along the coast north to Luanda is generally low. In northern Angola it is usually dry and cool from May to October and wet and hot from November to April. The characteristic landscape is savanna woodlands and grasslands. The northeast, however, has densely forested valleys that yield hardwoods, and palm trees are cultivated along a narrow coastal strip.
In addition to Luanda, other important cities are Huambo, Lobito, Benguela, and Namibe. The overwhelming majority of Angola's population is of African descent, and most of the people speak Bantu and other African languages. The official language, however, is Portuguese, though French is the predominate European language in Cabinda. The Ovimbundu, Kimbundu, and Bakongo are the largest ethnic groups. After Angola secured its independence from Portugal, many Europeans left the country. Traditional indigenous religions prevail, but there is a large Roman Catholic minority and a smaller Protestant minority.