The Nile flows through the Egyptian cities of Cairo and Luxor.
The Nile is traditionally described as the world’s longest river, although measurements comparing it with the Amazon depend on how headwaters and river mouths are defined. It runs generally northward through northeastern Africa and empties into the Mediterranean Sea. Egypt’s settlements and agriculture have depended on the river for thousands of years because most of the country is desert.
The river has two principal tributaries: the White Nile, whose remote headwaters are in the Great Lakes region of East Africa, and the Blue Nile, which rises in Ethiopia. They meet at Khartoum in Sudan. The Blue Nile carries much of the seasonal water and sediment historically associated with the annual flood.
The Aswan High Dam, completed in the 1970s, greatly reduced flooding and created Lake Nasser, but it also trapped sediment that once replenished farmland downstream. Cairo lies near the Nile Delta, while Luxor stands farther south beside major ancient Egyptian temple and tomb complexes.