The Amazon is a vast rainforest, the largest on the planet, comprising an expansive system of rivers that covers more than half of Brazil, and invades large tracts of its neighbouring countries. The Rio Solimoes is a powerful navigable stretch of river that enters Brazil from Peru, just above the city of Manaus. Close to the city, the light brown muddy river meets the Rio Negro with its darker waters and the two converge to form the mighty Rio Amazonas, which flows through Brazil to Belem.

Manaus is the gateway for excursions into the jungle and river system, situated as it is in the middle of the forest. From the city, scores of operators run day trips and longer boat tours for visitors wishing to experience Amazonian flora and fauna and meet the 'caboclos' (residents of the river towns). The city itself does not have many attractions, apart from some interesting buildings like its opulent and famous opera house, which dates from the height of the rubber boom in 1896. As the commercial hub of the state of Amazonas, it is very busy, with a noisy and crowded port and several bustling markets.

The Amazon and its tributaries together create approximately 30,888 square miles (80,000 sq km) of navigable river systems. Large areas of the Amazon forest still remain unexplored, however, and tens of thousands of rare and unknown species of animals, birds, insects, fish and plants are sheltered in and beneath the thick tree canopies.