The Nile is a major river in northeastern Africa that flows north. It empties into the Mediterranean. The Nile is the longest river in Africa and has long been thought to be the longest river in the world, though research suggests that the Amazon River is slightly longer. In terms of annual flow in cubic metres of water, the Nile is one of the world's smallest rivers. Its drainage basin is approximately 6,650 km (4,130 mi) long and spans eleven countries: the Democratic Republic of the Congo, Tanzania, Burundi, Rwanda, Uganda, Kenya, Ethiopia, Eritrea, South Sudan, Republic of the Sudan, and Egypt. The Nile, in particular, is the primary source of water for Egypt, Sudan, and South Sudan. Additionally, the Nile is an important economic river, supporting agriculture and fishing.