Olduvai Gorge is an archaeological site located in the eastern Serengeti Plains, which is in northern Tanzania. The gorge is a very steep sided ravine roughly 30 miles long and 295 ft. deep. Exposed deposits show rich fossil fauna, many hominid remains and items belonging to the one of the oldest stone tool technologies, called Olduwan. The time span of the objects recovered date from 2,100,000 to 15,000 years ago.

The main Olduvai Beds are in a lake basin about 16 miles in diameter. The rocks under the basin date to 5.3 million years ago. There have been seven major Beds distinguished they are ranked from oldest to youngest; Bed I, Bed II, Bed III, Bed IV, the Masek Beds, the Ndutu Beds, and Baisiusiu Beds.

Bed I dates to 2,100,000 years old and is 197 feet thick. It is mainly formed of lava flows, volcanic-ash deposits and other sediments. The upper part of the bed contains varied fauna and evidence of the Olduwan industry. Skeletal remains of hominids are assigned to the Homo Habilis an Australopithecus Boisei families. Campsites and what is believed to be a butchery site have also been excavated from this bed.

The Hominid living sites in Bed I are found mainly where streams from the volcanic highlands carried fresh water to Olduvai lake. The conditions for the preservation of the sites is mainly due to the ash falls from the nearby volcanoes and the inconsistency of the lake's depth. The debris found at the sites are various Olduwan tools, bone and teeth from animals, mainly from fair sized antelopes. Also a loosely built circle of lava blocks was found, suggesting that crude shelters were formed here as well.