Lake Eyasi is a seasonal shallow endorheic salt lake on the floor of the Great Rift Valley at the base of the Serengeti Plateau, just south of the Serengeti National Park and immediately southwest of the Ngorongoro Crater in the Crater Highlands of Tanzania. The lake is elongated, orientated southwest to northeast, and lies in the Eyasi-Wembere branch of the Great Rift Valley.
Seasonal water level fluctuations in the lake are dramatic, though the northwestern shore is constrained by the cliffs of the Serengeti Plateau. During the dry season the lake may dry up almost entirely, especially in drier years, so that Datooga , Maasai herders and Hadza foragers will cross the lake on foot, but in heavy rains it may flood its banks and attract hippopotamus from the Serengeti. It is a seasonal stop for migrating flamingos. The lake supports minor local fishing in wet years, but more often catfish and lungfish are taken from the streams and springs that feed the lake.
The Hadza are the indigenous inhabitants of the lake. They are found along most of the perimeter, but other tribes like the Datooga, the Isanzu , the Sukuma and the Iraqw lives in around the lake too.
If you visit Lake Eyasi, you can also see Mumba Cave which is an archaeological site that is located by the shores of Lake Eyasi. The site has yielded a number of Middle Stone Age and Late Stone Age artifacts.