The Yukon Quest International Sled Dog Race spans some of the harshest winter territory on the planet: 1,000 miles between Fairbanks, Alaska and the city of Whitehorse in Canada's Yukon Territory.

Known as 'The World's Toughest Sled Dog Race,' it's an event like no other, crossing four mountain ranges, including the intimidating 3,685-foot Eagle Summit, as it loosely follows the course of the mighty Yukon River.

Helen Hegener has followed the race since 2007, and in this Yukon Quest Album she shares her favorite stories and photos from this premier sled dog race.