The Iron Dog Professional Class is a highly competitive race. It is the World’s longest, toughest, snowmobile race in the world. The race course spans over 2,000 miles on some of Alaska’s most rugged terrain. Each Pro-Class race team consists of two racers and two snowmachines that are released at the Race Start in Big Lake at two minute intervals. Pro-Class riders are required to take a minimum of three layovers in specific locations for a total of 28 hours. This event does not require any qualifying race to enter. The course follows the Historic Iditarod Trail and continues on, with a finish in Fairbanks. This is a team race, consisting of two persons, and two snowmobiles (track driven and ski steered). Participants travel north from Big Lake to Nome, then south to Fairbanks, Alaska for a total of 1,971 miles.