The Nile is credited as the longest river in the world. Its main source is Lake Victoria in east central Africa. From its farthest stream in Burundi, it extends 6,695 km (4,160 miles) in length.
The two longest rivers in the world are the Nile, flowing into the Mediterranean, and the Amazon, flowing into the South Atlantic. Which is the longer is more a matter of definition than simple measurement.
Not until 1971 was the true source of the Amazon discovered, by Loren McIntyre (USA) in the snow-covered Andes of southern Peru.
The Amazon begins with snowbound lakes and brooks-the actual source has been named Laguna McIntyre-which converge to form the Apurimac.
This joins other streams to become the Ene, the Tambo and then the Ucayali. From the confluence of the Ucayali and the Marañón the river is called the Amazon for the final 3,700 km (2,300 miles) as it flows through Brazil into the Atlantic Ocean.
The Amazon has several mouths, which widen towards the sea, so that the exact point where the river ends is uncertain. If the Par estuary (the most distant mouth) is counted, its length is approximately 6,750 km (4,195 miles).