The Amazon River it is the longest undammed river in the world—and you won't believe when they built its first bridge!

The Amazon River in South America is the largest river in the world, averaging a discharge of about 209,000 cubic meters per second, which is greater than the next seven largest independent rivers combined! It is the longest undammed river in the world, not being dammed along its entire length. It used to be the longest un-bridged river until 2010, when the first bridge was opened over the Rio Negro.

The width of the Amazon is between 1.6 and 10 kilometers at is lower stages but during the wet seasons it expands to approximately 48 kilometers. The river flows into the Atlantic Ocean in a broad estuary that is about 240 kilometers wide. Because the Amazon is so long and wide, it is sometimes called The River Sea. The most distant source of the Amazon is a glacial stream on a snow capped peak called Nevado Mismi in the Peruvian Andes.

More than one-third of all known species in the world live in the Amazon Rainforest, which is a giant tropical forest and river basin with an area that stretches more than 5,400,000 square kilometers. In terms of biodiversity, it is considered the richest tropical forest in the world. Over 2,100 species of fish is known to live in the Amazon Basin, but more are being discovered every year.

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