Which East African lake is the world's largest permanent desert lake?

Lake Turkana is the world’s largest permanent desert lake.

It occupies the Kenyan Rift Valley, with its northern end extending into Ethiopia. The lake covers about 6,400 square kilometres and is an endorheic basin: rivers flow in, but there is no significant surface outlet, so evaporation removes most of its water. Its hot, arid setting and year-round water distinguish it from temporary desert lakes.

Lake Turkana is also the world’s largest alkaline lake. Its principal inflow is Ethiopia’s Omo River, supplemented by Kenya’s Turkwel and Kerio rivers. Because evaporation is intense, the lake is slightly saline and generally unsuitable as a dependable drinking-water source.

The lake’s shores and islands are globally important for wildlife and archaeology. Nile crocodiles, fish and many waterbirds live there, while nearby sites have yielded abundant hominin fossils. Sibiloi, Central Island and South Island national parks form part of a UNESCO World Heritage site. Falling water levels and changes to Omo River flows have raised serious environmental concerns.