There are many long rivers in the world, but which ones are the longest? There is disagreement over which river is the longest one in the world. Some claim it is the Nile River while others say it is the Amazon. This debate is due to the difficulty regarding determining the length of a river and also that measurements differ according to who measured them. Another cause of disagreement is that some scientists do not include tributaries of the rivers in their measurements.
The Nile River, located in Africa, is listed as 6,655 kilometers (4,135 miles) long. The Amazon River is often listed as 6,516 kilometers (4,049 miles) long. However, Brazilian scientists claimed to have found the real source of the Amazon. If they are right, then that river is the longest in the world at 6,800 kilometers (4,225 miles) long.
The third longest river in the world is the Chang Jiang River – also known as the Yangtze – found in China. The Yangtze is 6,380 kilometers (3,964 miles) in length. It begins in western China and opens into the China Sea near Shanghai.
The Mississippi-Missouri River system is considered the fourth longest in the world and the longest in the United States at 5,969 kilometers (4,709 miles). Although each river separately would not be in the top five, the two rivers are grouped together into one because the Missouri River meets the Mississippi River near the city of St. Louis.
The Ob-Irtysh River is made up of the Ob and its main tributary, which is Irtysh. At 5,568 kilometers (3,459 miles) it is the world’s fifth longest river. Starting in the Altai Mountains in Russia, the river opens into the Gulf of Ob.
The Yenisey-Angara-Selenga Rivers join together to form the sixth longest river system at 5,550 kilometers (3,448 miles). It runs through Siberia and is considered a boundary between the west and east sections of the region. Its mouth is at the Arctic Ocean.
Huang He, which is also known as the Yellow River because of the color of its silt, is the seventh longest river in the world. Located in China and 5,464 kilometers (3,395 miles) long, the river begins in the Kunlun Mountains and empties into the Gulf of Bohai.
The Congo River in Africa is the eighth longest river at 4,667 kilometers (2,900 miles). It makes up a large part of the border between the Republic of Congo and Zaire. The Congo empties into the Atlantic Ocean.
Universe Today has articles on the longest river and what is the world’s widest river.
Astronomy Cast has an episode on Earth.
Google Book: Seven Natural Wonders of Central and South America
The Nature Conservancy
How Stuff Works
About.com – Longest Rivers
Louisiana State University
New World Encyclopedia