Amazon basin
The Amazon Basin is the part of South America drained by the Amazon River and its branches. It is low-lying in relation to sea level.
The river has its origens high up in the Andes of Peru and Ecuador. More than half of this drainage basin (54%) is in Brazil, including the lower part. Other portions are tributaries from Colombia, Venezuela and Bolivia.
The Amazon rainforest is the largest in the world, covering about 8,235,430 km2 (3,179,720 sq mi) with dense tropical rain forest. It is also known as Amazonia. This is one of the world's most important ecosystems.