What is the Amazon River?
The Amazon is the largest river in the world by volume, carrying about 20 percent of all river water that flows into the oceans. It flows about 6,400 kilometers across South America to the Atlantic.
The Amazon begins high in the Andes Mountains of Peru and flows east through Colombia and Brazil. It is fed by more than 1,000 tributaries, several of which are among the world's largest rivers. During the rainy season, parts of the river can be more than 40 kilometers wide.
It is usually ranked the second-longest river after the Nile, but some studies using different starting points suggest the Amazon may be longer. There are no bridges across the main Amazon River, partly because it flows through rainforest with few roads and its banks shift.
The Amazon basin
The river drains the Amazon basin, which holds the largest tropical rainforest on Earth. The rainforest is home to around 10 percent of the world's known species, including pink river dolphins, piranhas, giant otters and jaguars. Deforestation and drought are major threats to the region.
Did You Know?
At its mouth, the Amazon releases so much fresh water that the sea stays less salty more than 100 kilometers offshore.