According to National Geographic, three major land regions exist on the continent of South America: the coastal plains, the river basins and the mountains and highlands. The continent is a study of geographical diversity, home both to the driest place (Atacama Desert) and the longest river (Amazon) in the world.
The coastal plains are located along the Atlantic Ocean on the east and the Pacific Ocean on the west. Many of these low-lying, flat areas are very dry. Three major river basins, the Orinico, the Amazon and the Paraguay/Parana, cover more than 4 million square miles. The Amazon rain forest is part of the Amazon river basin. The mountains and highland regions are comprised primarily of the Andes Mountains, the Brazilian Highlands and the Guiana Highlands.