The dog sled was invented by the indigenous peoples of the Far North to travel in winter before being used by the early European explorers and trappers to transport goods over snowy terrain. Packs of two to twelve dogs, sometimes more, are tied, in pairs, to a central line, connected to the sled. Off piste in deep snow, the dogs can be placed in a single file between two draft lines and follow the narrow trail opened by the musher on snowshoes. Fan hitches, where each dog is attached to the sled by its own draft line, are reserved for large, open spaces where the snow accumulates and hardens.