It is named after the Iditarod Trail, an old mail and supply route, traveled by dogsleds from Seward and Knik to Nome, Alaska. March 18, 2015 - Dallas Seavey is the winner of the 43rd annual Iditarod. His father, Mitch Seavey, is the runner-up. March 11, 2014 - Dallas Seavey is the winner of the 42nd annual Iditarod. Facts: The race ranges from 975 to 998 miles long, based on whether the southern or northern route is being run. The length can also vary from year to year based on course conditions.