The Amazon basin is drained by the Amazon River. The Amazon River is the largest river in the world and flows through many countries in South America, eventually emptying into the Atlantic Ocean.

Amazon River
The Amazon basin is drained by the Amazon River, which is the largest river by discharge volume of water in the world. It flows through South America and plays a crucial role in the region's ecosystem and biodiversity.

Importance
- The Amazon River basin is home to a wide variety of plant and animal species, many of which are not found anywhere else on Earth.
- It is a vital waterway for transportation and commerce for the countries it passes through, including Brazil, Peru, and Colombia.
- The river also supports the livelihoods of millions of people who depend on it for fishing, agriculture, and other resources.

Length and Size
- The Amazon River is approximately 4,345 miles (7,062 kilometers) long, making it the second-longest river in the world after the Nile.
- It has a drainage area of around 7,050,000 square kilometers, which is larger than the next seven largest rivers combined.

Ecological Importance
- The Amazon River basin is often referred to as the "lungs of the Earth" because of the vast amount of oxygen that is produced by the rainforest that surrounds it.
- The river and its tributaries are home to countless species of plants, animals, and insects, many of which have not yet been discovered by scientists.
In conclusion, the Amazon River is a critical waterway that plays a significant role in the biodiversity, economy, and ecological health of the Amazon basin and South America as a whole.