In one of the final great feats of dog sleds, twenty drivers and teams carried the life-saving serum 674 miles (1,085 km) in 127 hours.

From Unalakleet, the trail coursed north and west around the shore of the Seward Peninsula, passing the villages of Shaktoolik, Koyuk, and Golovin.

When explorers and prospectors arrived in the north, they quickly learned from Native Alaskans that sled dog teams were the only way to reliably move goods and people across the frozen landscape.

Not by chance, the "Seward to Nome Trail" as the Iditarod was originally called, was first mapped and marked in 1908 by a four-person Alaska Road Commission crew supported by dog teams.

... having two basket sleds and 18 sets dog harness made ... at Seward we spent five days 'trying out dogs' and repacking the outfit ready for the trip ...Nine months after the route was surveyed, two prospectors made a 'Christmas Day Strike' in the Iditarod Mining District, and the last great gold rush was on.

New winter mail contracts bypassed the fading town of Iditarod in favor of more direct routes to Nome, and World War I drew young miners and workers away from the gold fields.

Twenty of Alaska's best mushers and their teams carried the serum 674 miles (1,085 km) from Nenana to Nome in just over 127 hours.

With downturns in gold mining, most of the roadhouses closed, boom towns emptied, and the Iditarod Trail fell into disuse.

After years of effort by Redington and the Alaska Congressional delegation, the Iditarod was designated as a National Historic Trail in 1978.

[4] Every year local groups, community clubs and individuals contribute time and money to maintain and improve the Iditarod Trail.

Today the race follows much of the primary route of the Iditarod National Historic Trail, with a segment alternating north or south, depending on the year.

Every odd year (i.e., 2011), the race travels the south route from Ophir to Kaltag through the ghost town of Iditarod.