Iditarod Trail Sled Dog Race

Justin Savidis dogs await lineup in the musher lot before the official restart of the Iditarod dog sled race in Willow, Alaska. The nearly 1,000-mile (1,600-km) Iditarod Trail Sled Dog Race commemorates a 1925 rescue mission that carried diphtheria serum by sled-dog relay to the coastal community of Nome, which remains the final destination in this 42nd edition of the event.

Nathaniel Wilder/Reuters

Justin Savidis dogs await line-up in the musher lot before the official restart of the Iditarod dog sled race in Willow, Alaska. The nearly 1000-mile Iditarod Trail Sled Dog Race commemorates a 1925 rescue mission that carried diphtheria serum by sled-dog relay to the coastal community of Nome, which remains the final destination in this 42nd edition of the event.