The Andes are the longest continental mountain range on Earth, stretching along western South America.
The range extends for about 7,000 kilometers through seven countries: Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile, and Argentina. It formed mainly through the subduction of the Nazca Plate beneath the South American Plate, a process that continues to produce earthquakes and volcanic activity.
The Andes are not one uniform wall of mountains. They include several parallel ranges, high plateaus such as the Altiplano, deep valleys, glaciers, deserts, and some of the world's highest volcanoes. Aconcagua, in Argentina, is the highest peak in both the Andes and the Western Hemisphere.
A common mix-up is confusing the Andes' great length with the Himalayas' greater maximum elevation. Mount Everest is higher than any Andean summit, but the Andes extend much farther from north to south.