The Andes is the longest mountain range on land, running down western South America.

The longer version

Long mountain chains form where a plate boundary runs for thousands of kilometres. Here an oceanic plate slides beneath a continental one, and the compression folds and lifts the edge into a continuous belt. Volcanic activity accompanies the process, building peaks on top of the folded rock. Uplift continues today.

Because the range runs north to south across many latitudes, it contains glaciers, high plateaus, deserts and rainforest within one chain. Altitude shapes settlement, with people adapting to thin air at high elevations. Minerals concentrated by volcanic heat have long drawn mining to the region, and terraced farming on the slopes goes back a very long way.

Where this entry sits

These facts wander across maps, borders, deserts, rivers, mountains, and the extreme corners of the natural world. Each one is short and self-contained, offering a small surprise about places you may never visit rather than anything you actually need. The full list sits on the Geography page, where every entry is listed in order.