Cerro Castor, Mountain summit in Tierra del Fuego, Argentina

Cerro Castor is a summit in Tierra del Fuego, Argentina, located about 16 miles (26 km) from Ushuaia, with ski runs cut through sub-Antarctic forest. The slopes face north and descend through mixed woodland, with open terrain at the top and tree-lined runs lower down.

The ski resort at Cerro Castor opened in the late 1990s as the first purpose-built winter sports facility in Tierra del Fuego. Its development brought a new wave of visitors to this part of Patagonia at a time when the region had few tourist options beyond the city of Ushuaia.

The resort's name comes from the beaver (castor), introduced to Tierra del Fuego in the mid-20th century; the animals have since altered large areas of forest. The slopes run through a lenga beech forest, and the resort also hosts events such as the Interski Congress and World Cup, held here in September 2015, the association's first event in the Southern Hemisphere.

The slopes are open from mid-June to mid-October, and outside of winter the summit area is not easily accessible. Shuttle buses run regularly from Ushuaia during the season, and warm, waterproof layers are worth bringing regardless of the forecast.

Cerro Castor is considered the southernmost ski resort in the world, which means visitors from the northern hemisphere can ski here in the middle of their own summer. The July school holiday season in Europe and North America lines up almost perfectly with the peak of winter here.