The Andes are the longest continental mountain range, stretching for roughly 7,000 kilometers along South America's western edge.
The range runs through Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile, and Argentina. It formed through the subduction of the Nazca and Antarctic oceanic plates beneath the South American Plate, a process that continues to produce earthquakes, volcanoes, uplift, and dramatic highland landscapes.
The Andes are not a single narrow ridge. They include several parallel cordilleras, high plateaus such as the Altiplano, deep valleys, deserts, cloud forests, and glaciated peaks. Aconcagua in Argentina rises to about 6,961 meters and is the highest mountain in both the Andes and the Western Hemisphere.
A common mix-up is confusing the Andes with the Himalayas. The Himalayas contain Earth's highest summit, Mount Everest, but the Andes are longer as a continental range. If submarine mountain systems are included, the global mid-ocean ridge is longer, but it is not the answer to this land-based geography question.