NGORONGORO:
Set in Northern Tanzania, sharing part of the Serengeti plains to the north-west and with the towns of Arusha and Moshi, and Mount Kilimanjaro to the east, Ngorongoro forms part of the unique Serengeti ecosystem.

A major ecological survey of the Serengeti Reserve (which then included Ngorongoro) in the late 1950s resulted in the establishment of the Ngorongoro Conservation Area (NCA) in 1959.
This was a pioneering experiment in multiple land use where pastoralism, conservation and tourism could co-esixt. At the same time the Serengeti National Park was enlarged and extended northwards to the Kenya border, where it borders the Masai Mara.

Subsequently awarded World Heritage Site and International Biosphere Reserve status, the NCA covers an area of 8292 sq km and ranges in altitude from 1020m to 3587m.

The terrain embraces several distinct habitats from open grasslands to mountain forest, and from scrub bushland to highland heath. The area contains sites of international palaeontological and archaeological importance. Around 25000 animals live in the Crater throughout the year, whilst in the NCA as a whole the numbers can swell to more than 2.5 million, depending on the season.

The NCA aims to maintain the historic balance of people and nature in a way which has not been possible in many parts of Africa. At stake are the rich biodiversity and ecology of the Serengeti Plains and Ngorongoro highlands, the major palaeontological and archaeological sites and the vital water catchment areas. Within all this, man and wildlife have to live together without harm or destroying each other's habitats.

Man and his ancestors have lived in the Ngorongoro ecosystem for more than 3 million years. Evidence of a regional hunter-gatherer culture dates back 17000 years and it is clear that various tribes have migrated in and out of the area, just as they have done in relatively recent times. By careful management and continuing research, the fragile balance between man and nature is successfully maintained.

History:
Two main geological rifts run through the area. Nine volcanoes in the Ngorongoro highlands were formed during the past 4 million years. One of these, Oldonyo Lengai (Mountain of God) is still active.

Over millennia the ash and dust from each eruption has been carried by the winds to form the fertile soils of the Serengeti plains.

The earliest sign of mankind in the NCA is at Laetoli where hominid footprints are preserved in volcanic rock 3.6 million years old. Further north, Olduvai Gorge has yielded a wealth of hominid and animal remains.

The Crater:
The jewel in Ngorongoro's crown is a deep volcanic crater - the largest unflooded and unbroken caldera in the world - 19.2km in diameter, 610m deep and 304 sq km in area. The rich pasture and permanent water of the Crater floor supports a large resident population of wildlife of up to 25000 - predominantly grazing - animals. These include wildebeest, zebra, gazelle, buffalo, eland, kongoni and warthog. The swamps and forest provide additional resources for hippo, elephant, waterbuck, reedbuck and bushbuck, baboons and vervet monkeys. The steep inner slopes provide a habitat for dikdik and the rare mountain reedbuck. Jackals thrive in the crater and bat-eared foxes live in the short grass areas. Predatory animals - lion, leopard, cheetah, serval cats - live off the abundant wildlife, and large packs of hyena roam the crater, making their own kills and scavenging from others. The crater is a dynamic and constantly changing ecosystem and the numbers and proportion of some animals has fluctuated considerably over the past 30 years.