Lake Chad Lake Chad is a freshwater lake located in the Sahelian zone of west-central Africa. It is located in the interior basin which used to be occupied by a much larger ancient sea sometimes called Mega Chad. The lake is historically ranked as one of the largest lakes in Africa. However, its surface area varies by season and as well as from year to year. Lake Chad is mainly in the far west of Chad, bordering on northeastern Nigeria. The Chari River, fed by its tributary the Logone, provides over 90% of the lake's water, with a small amount coming from
Nigeria (), Niger (), Chad (), Cameroon (), and has a coastline of at least s. Nigeria lies between latitudes 4° and 14°N, and longitudes 2° and 15°E. The highest point in Nigeria is Chappal Waddi at . The main rivers are the Niger and the Benue, which converge and empty into the Niger Delta. This is one of the world's largest river deltas, and the location of a large area of Central African mangroves. Nigeria has a varied landscape. The far south is defined by its tropical rainforest climate, where annual rainfall is a year. In the southeast stands the