Which mountain range runs through the entire Patagonia region? The Andes. Patagonia occupies the southern part of South America, spanning portions of Argentina and Chile, and the Andes form its mountainous western backbone.
The range follows the continent’s Pacific side and includes the Southern Andes, whose landscapes shape much of Patagonia’s geography. West of the mountains are fjords, temperate rainforests, lakes, and extensive ice fields; eastward, the land generally descends into drier tablelands and steppe.
The Andes are not a single uniform wall. They consist of connected cordilleras, valleys, plateaus, volcanoes, glaciers, and individual massifs. In Patagonia, major features include the North and South Patagonian Ice Fields and celebrated peaks such as Fitz Roy and Cerro Torre.
A frequent mistake is choosing the Rocky Mountains because they are another major range in the Americas. The Rockies lie in western North America, while the Andes extend along the western edge of South America. Patagonia’s northern boundary is debated, but wherever the region is drawn, the Andes are its defining mountain system.