The Nile is the river most commonly identified as the longest in the world, measuring about 6,650 kilometres (4,130 miles).
It flows northward through northeastern Africa to the Mediterranean Sea. Its principal modern tributaries include the White Nile, which rises in the Great Lakes region, and the Blue Nile, which begins at Lake Tana in Ethiopia. They meet at Khartoum in Sudan before the river continues through Egypt.
The Nile supported ancient Egyptian civilization by providing water, transport, fish, and fertile soil deposited by seasonal floods. The Aswan High Dam, completed in 1970, greatly changed the river's flooding pattern and created Lake Nasser.
Some measurements place the Amazon first, depending on how its source and mouth are defined. That ongoing geographical debate is why the Nile's status is often described as the commonly accepted, rather than universally undisputed, record.