Dog sledding. I think it is the toughest.
no of corse by alot
They are required so that the dogs feet wont get hurt by the cutting ice and the hard packed snow injuries
The Iditarod Trail Sled Dog Race, usually just called the Iditarod, is an annual sled dog race in Alaska, where mushers and teams of typically 16 dogs cover 1,161 miles (1,868 km) in eight to fifteen...