The Ngorongoro crater at 2286 metres above the sea- level, it is the largest unbroken caldera in the world. The crater, which formed when a giant volcano exploded and collapsed on itself some two to three million years ago, is 610 m (2,000 ft) deep and its floor covers 260 km2 (100 sq mi). Estimates of the height of the original volcano range from fifteen to nineteen thousand feet (4500 to 5800 metres) high. Surrounded by very steep walls rising 610 metres from the crater floor, this natural amphitheatre covers an area of about 260 sq km (100 sq miles) and is home to 25000 larger mammals .
Almost half of them are zebras and gru. There are also gazelles, buffaloes, elands and wart hogs. Such vast numbers attract plenty predetors, mainly lions and hyenas but also cheetahs and leopards.
More than 100 species of birds not found in the Serengeti have been found here . Aside from herds of zebra, gazelle, and wildebeest, the crater is home to the "BIG FIVE" Rhino's, Lions, Leopards, Elephants and buffalo's. The creater has been declared a world heritage by UNESCO . The land in the Ngorongoro Conservation Area protects the Wildlife while allowing human life to continue as well as Olduvai George which is believed to be seat of humanity after the discovery of the earliest known specimens of the human genus.