Ski resorts are developed for skiing, snowboarding, and other winter sports. Ski resorts are located in both the northern and southern hemispheres on all continents except Antarctica. Most ski resorts are outdoor, but there are also a number of indoor facilities. In Europe, most ski resorts are towns or villages in or adjacent to a ski area: a mountainous area with pistes (ski trails) and a ski lift system. In North America, it is more common for ski areas to exist well away from towns, so ski resorts usually are destination resorts, often purpose-built and self-contained, where skiing is the main activity.