The Amazon River is conventionally identified as the longest river in South America.
The river flows across the continent from the Andes of Peru through Brazil before entering the Atlantic Ocean. Its enormous drainage basin covers roughly 7 million square kilometres and includes parts of several countries. The Amazon carries more water than any other river on Earth, making it especially significant in global hydrology.
The exact length of the Amazon has been debated because researchers differ over which headwater stream counts as its true source. Some measurements place it longer than the Nile, while many standard references continue to rank the Nile first overall. That measurement debate does not change the Amazon’s status as South America’s dominant river system.
The river’s name comes from Spanish reports comparing Indigenous warrior women to the Amazons of Greek mythology. Its basin supports extraordinary biological diversity and contains vast areas of seasonally flooded forest.