The Amazon, which drains much of South America, is the world's largest river measured by volume of water. It's 6,400 km long
In its great basin of 7 million square kilometres flows a fifth of all the river water returning to the oceans.
Its source is in the Andes mountains of western South America and its giant mouth is on the eastern coast. It has 1,100 large tributaries (each bigger than the Thames).
