Okavango Delta

A vast inland delta where a river fans out into the Kalahari instead of the sea, a haven for wildlife.

It was named one of the Seven Natural Wonders of Africa on 11 February 2013, and on 22 June 2014 it became the 1,000th site on the UNESCO World Heritage List. Each year about 11 cubic kilometres of water spreads over 6,000 to 15,000 square kilometres. Nearly all of it disappears into the air or the ground, and only a little leaves through the Thamalakane and Boteti rivers.

A flood that arrives in the dry season

Rain falls in the Angolan highlands in January and February, and the surge travels about 1,200 kilometres in around a month, then spreads over the delta over the next four months. Flood levels peak between June and August, in Botswana's dry winter, when the delta swells to three times its permanent size. Animals come from kilometres around, creating one of Africa's greatest concentrations of wildlife. The land is so flat that its height varies by less than 2 metres.

Islands made by termites

The delta has thousands of islands. About 70 percent of them began as termite mounds, where a tree then took root. Salt collects around the roots and leaves white barren patches in the middle of many islands. The largest, Chief's Island, was lifted by a fault line, is over 70 kilometres long and 15 kilometres wide, and was once a hunting area for a chief. Today it is a core refuge for wildlife when the waters rise.

Wildlife of the delta

All of the big five game animals live here: lion, leopard, African buffalo, elephant and rhinoceros. The most abundant large mammal is the red lechwe, with about 88,000 animals. The delta hosts over 400 bird species and 71 fish species, including the tigerfish, and 1,068 plant species. Its water supports this life even though the average rainfall is only 450 millimetres a year.

On the globe

The model shows winding water channels and green islands spreading out in the dry land; look for the fan of water in the Kalahari.