Vasaloppet is an annual long distance cross-country ski race held on the first Sunday of March. The 90 km (56 mi) course starts in the village of Berga, just south of Sälen in western Dalarna, Sweden, and ends in the town of Mora in the central part of the province. It is the oldest cross-country ski race in the world, as well as the one with the highest number of participants.

Competitive cross-country skiing encompasses a variety of race formats and course lengths. Rules of cross-country skiing are sanctioned by the International Ski Federation and by various national organizations. International competitions include the FIS Nordic World Ski Championships, the FIS Cross-Country World Cup, and at the Winter Olympic Games. Such races occur over homologated, groomed courses designed to support classic (in-track) and freestyle events, where the skiers may employ skate skiing. It also encompasses cross-country ski marathon events, sanctioned by the Worldloppet Ski Federation, and cross-country ski orienteering events, sanctioned by the International Orienteering Federation. Related forms of competition are biathlon, where competitors race on cross-country skis and stop to shoot at targets with rifles, and paralympic cross-country skiing that allows athletes with disabilities to compete at cross-country skiing with adaptive equipment.