The Ngorongoro is a collapse crater in Tanzania on the edge of the Serengeti. The crater floor lies at around 1,700 metres, the crater rim at around 2,300 metres. The diameter of the crater is between 17 and 21 kilometres

The formation of the Ngorongoro Crater is closely linked to the formation of the East African Rift Valley. This began to open about 18 million years ago, causing large areas in the area of today's rift valley to sink. In the course of the rift valley opening, today's volcanic highlands of the Ngorongoro, where numerous volcanoes once existed, were formed. Around 2.5 million years ago, the Ngorongoro volcano was at its most active. It is assumed that it was comparable to a stratovolcano, the equivalent of Kilimanjaro, some 200 kilometres away. Its slopes probably towered around 3,000 metres above today's crater rim, making it similar in size to Kilimanjaro.

The Ngorongoro and the surrounding savannah highlands have been settled by nomadic Maasai herdsmen since the 18th century at the latest and used for nomadic cattle grazing. The crater itself had great spiritual significance for the Maasai, and the Lerai Forest on the crater floor was used as a burial site, among other things

Since 1951, the crater has been part of the Serengeti National Park. In 1959, a special protected area was established outside the crater, in which the Maasai are allowed to settle and graze. In 1975, agriculture was finally banned in the crater. In 1979, it was added to the UNESCO World Heritage List