Arid to semi-arid desert area, occupying a plateau and forming most of Botswana and extending into Namibia, Zimbabwe, and South Africa; area about 900,000 sq km/347,400 sq mi. The only permanent river, the Okavango, flows into a delta in the northwest, forming marshes that are rich in wildlife. The British explorer, David Livingstone, crossed the Kalahari in 1849.
The number of stripes changed frequently until around 1800. Red, white, and blue became the colours of liberty and an inspiration for other revolutionary flags around the world. Effective date: 19 February 1937.