The Serengeti ecosystem supports the greatest remaining concentration of plains game in Africa, including more than 2 million large mammals. The annual Great Migration of the animals from the Serengeti into Kenya in search of water and pastures is an amazing spectacle that attracts thousands of people worldwide. At times the column of wildebeest can be 40km in length and in the breeding season an explosion of 8 000 calves a day are produced. Serengeti is also Tanzania’s oldest Park and its vast open plains have adorned the covers and pages of magazines for decades and featured in numerous films and documentaries.

It is contiguous with Kenya’s Maasai Mara Game Reserve and stretches as far as Lake Victoria to the west. Arusha is 335 km away. Its name comes from the Maasai word Siringet, meaning “endless plains”. The Serengeti National Park covers an area of 14,763 square kilometres, which is equal in size to Northern Ireland. 

The annual migration of the wildebeest, zebra, and gazelle usually starts in May and is triggered by the end of the wet season. See The Great Migration for a more detailed account. Other mammal species found in this Park include Black rhino, buffalo, cheetah, elephant, eland, Thompson’s gazelle, giraffe, hippo, and a renown population of lion and leopard. The Seronera Valley is home to large prides of lions. The Park’s abundance of wildlife is also manifested in the insect world with 100 species of dung beetle alone.

Almost 500 species of birds have been recorded in the Park, some of them Eurasian migrants that are present from October to April. Both Greater and Lesser flamingos flock the saline lakes of Lagaja and Magadi.

The Serengeti National Park lies in a high plateau between the Ngorongoro highlands and the Kenya/Tanzania border, and extends almost to Lake Victoria. The Park encompasses the main part of the Serengeti ecosystem. The Serengetiecosystem extends into the following game reserves and conservation areas that surround the Park's boundaries: MaasaiMara National Park, Loliondo Controlled Area, Ngorongoro Conservation Area, Maswa Game Reserve, Grumeti Controlled Area, and Ikorongo Controlled Area; and is defined by the dominant migration route of the wildebeest in search of food and water. 

There are two shallow saline lakes in the Serengeti: Lagaja and Magadi. From the wildlife point of view the lakes are most notable for both Greater and Lesser flamingos, which feed on the minute plants and animals, which live in the mud of soda lakes. Kopjes are rock outcrops that are technically known as inselbergs. Kopjes consist of old granite rock that with time and erosion by weathering have smoothened into piles of rocks looking as though they are balanced on one another. These kopjes are pronounced, standing out against the open grassland plains, where the countryside has been more or less levelled off by deposits of dust and ash from volcanoes of the Great Rift Valley.