The Amazon carries about a fifth of all the river water that flows into the world's oceans.
Its discharge is greater than the next seven largest rivers combined. The fresh water pushes so far out to sea that early sailors could drink from the ocean more than 100 kilometres from the coast.
Why is this true?
The Amazon basin covers around 40 percent of South America and receives enormous rainfall year round. In the wet season the river can be more than 40 kilometres wide in places.
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