The Amazon basin is the part of South America drained by the Amazon River and its tributaries. The Amazon drainage basin covers an area of about 7,500,000 km2 (2,900,000 sq mi), or roughly 40 percent of the South American continent. It is located in the countries of Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, Suriname and Venezuela.
Most of the basin is covered by the Amazon Rainforest, also known as Amazonia. With a 5,500,000 km2 (2,100,000 sq mi) area of dense tropical forest, this is the largest rainforest in the world.
The Amazon River rises in the Andes Mountains at the west of the basin with its main tributary the Marañón River in Peru. It is usually considered to be the second longest river in the world. However, a team of Brazilian scientists has claimed that the Amazon is the longest river in the world. It covers about 6,400 km before draining into the Atlantic Ocean. The Amazon and its tributaries form the largest volume of water. The Amazon accounts for about 20% of the total water carried to the oceans by rivers. Some of the Amazon rainforests are deforested because of the increasing of cattle ranches and soy beans field.
The highest point in the watershed of the Amazon is the peak of Yerupajá at 6,635 m (21,768 ft).