Watch Natural World Season 20 Episode 15 Online

A look at the biggest river system on the planet, the Amazon, which rises as a small stream high in the Andes and ends over 6,000 miles away in the Atlantic Ocean. Holding a fifth of the Earth's river water, the Amazon floods an area larger than England and supports an unbeatable array of wildlife. The Amazon Basin is home to thousands of types of fish, including air-breathing species and the deadly piranha.