What is the longest mountain range above sea level?

The longest mountain range above sea level is the Andes. This immense continental range follows the western edge of South America for roughly 7,000–8,900 kilometres, depending on how its boundaries are measured.

The Andes pass through seven countries: Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile and Argentina. They are divided into northern, central and southern sections, with parallel cordilleras, high plateaus and deep valleys along their length.

The range formed mainly because the Nazca Plate and Antarctic Plate are being forced beneath the South American Plate. That ongoing subduction compresses and lifts the continent’s western margin, making the Andes geologically active and responsible for many volcanoes and earthquakes.

A common mix-up is the Mid-Ocean Ridge, which is longer overall but lies mostly underwater. The Himalayas are higher, and the Rocky Mountains are another major continental system, but neither is as long above sea level as the Andes. Aconcagua, in Argentina, is the range’s highest summit at about 6,961 metres.