The longest river in the world is the Nile. It is 4,160 miles long and is located in northeastern Africa. It passes through eleven countries including Uganda, Ethiopia and the Republic of Congo and is the primary water source for Egypt and Sudan.
The Nile has two major tributaries, the White Nile and the Blue Nile. Most consider the White Nile the primary stream of the Nile itself, while the Blue Nile is the holder of the river's most fertile soil and is the source of most of its water. Of the two tributaries, the White Nile is longer, with its most distant source located in Rwanda or Burundi.