The Niger River is an interesting location due to this. It is the third-longest river in Africa behind the Nile and the Congo. The impressive river also creates the Niger Valley, an area of arable, fertile land surrounded by otherwise infertile desert. The river is an invaluable source of water, fish, and hydroelectricity which has resulted in the establishment of many cities along its banks. These cities were built as trading hubs along the trans-Saharan caravan trade route, connecting West Africa to larger parts of the world.
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