The Amazon is a vast forest – the largest on the planet – and a giant river system. It covers over half of Brazil and a large portion of South America. The forest extends into Brazil’s neighbouring countries (Venezuela, Colombia, Peru and Bolivia), where the river itself begins life among thousands of different headwaters. In Brazil only the stretch between Manaus and Belém is actually known as the Rio Amazonas: above Manaus the river is called the Rio Solimões up to the border with Peru, where it once again becomes the Amazonas. It is by far the biggest river system in the world; eight of the world’s twenty longest rivers are in the Amazon basin, along with a fifth of the planet’s fresh water.
In its upper reaches, the Rio Solimões from Peru to Manaus, it is a muddy light brown, but at Manaus it meets the darker flow of the Rio Negro and the two mingle together at the famous “meeting of the waters” to form the Rio Amazonas. There are something like 80,000 square kilometres of navigable river in the Amazon system, and the Amazon itself can take ocean-going vessels virtually clean across South America, from the Atlantic coast to Iquitos in Peru.