The Cuito and Cubango Rivers converge at the southern Angolan border, forming a bigger river, the Okavango, which flows across the Caprivi Strip, a narrow band of Namibia, and into Botswana.

But it's really more like a miracle. Rains that fall in Angola during the previous wet season, from November through May, propel the Okavango River along its 1,000-mile downhill course in June ...

The river's source is in Angola – where it's also known as the Cubango River – and when it gets further south to Botswana, it drains into an enormous area of wetlands called the Okavango Delta.