The Nile flows through Cairo and forms a large delta before entering the Mediterranean Sea.
At about 6,650 kilometres, the Nile is commonly described as the world’s longest river, although measurements comparing it with the Amazon depend on which source and tributaries are counted. The river runs generally northward through northeastern Africa and has supported settled societies for thousands of years.
The Nile has two major tributaries: the White Nile, whose farthest headwaters are in the Great Lakes region, and the Blue Nile, which begins at Lake Tana in Ethiopia. They meet at Khartoum in Sudan, then the united river continues through Egypt.
The Nile Delta begins north of Cairo and spreads into a fertile fan-shaped region on Egypt’s Mediterranean coast. The Aswan High Dam, completed in 1970, regulates flooding and produces hydroelectric power, but it also reduced the natural delivery of sediment to the delta.