Lake Chad is an endorheic freshwater lake located at the junction of four countries: Nigeria, Niger, Chad, and Cameroon in western and central Africa respectively, with a catchment area of 1×10^6 km2 (390,000 sq mi). It is an important wetland ecosystem in West-Central Africa. The lakeside is rich in reeds and swamps, and the plain along the lake is fertile, making it an important irrigated agricultural area. The lake is rich in aquatic resources and is one of the important freshwater fish producing areas in Africa.

The Chari River, or Shari River, is a 1,400 kilometres (870 mi) long river, flowing in Central Africa. It is Lake Chad's main source of water.