Andes

An 1856 physical map of South America, showing the Andes along the western coast.
(CC) Image: Cartography Associates

The Andes mountain range runs the entire length of the Pacific coast of South America. It is the longest range in the world, extending from Venezuela and Colombia in the North through Ecuador, Peru and Bolivia to Southern Chile and Argentina. The geological composition of the range is the result of a number of different processes over geological time, but the current shape and position of the chain is the result of the tectonic collision of the Nazca plate and the South American Plate.