The Alaskan Iditarod commemorates the "Great Mercy Race" of January 1925 which unfolded when Dr. Curtis Welch diagnosed several cases of diphtheria in Nome. The nearest source of serum was over 900 miles away in Anchorage. Since airplanes of the era were unsuitable to fly in Alaska's harsh winter weather, a land relay system using 20 Mushers and their dog teams was set up via radio and telephone to deliver the medication to Nome.
The serum was delivered 250 miles by train from Anchorage to Nenana where the first relay team picked up the serum and headed for Nome 674 miles west. At the same time Nome's greatest Musher, Leonhard Seppala, drove east with his best lead dog "Togo" and a team of 20 dogs. Along the way Seppala dropped dogs off at several points so he would have fresh animals on his return trip. To save time Seppala crossed the Norton Sound and met a westbound musher outside Shaktoolik.
The weather changed dramatically when Seppala and Togo began their 150-mile return trip to Nome. A blizzard began blowing across the sound, cutting visibility to zero and the temperature dropped to minus 30 degrees. Under these conditions the ice could break up at any time and the precious cargo would drift out to sea.
Sapalla, knowing that there was no shorter way back and time was essential to the stricken children in Nome, decided to backtrack across the Sound. The loud wind made it impossible for Sappala to hear any sound of breaking ice and he had to trust Togo's keen sense of smell and direction to lead the team across the dangerous ice. When they reached the west side of the Sound Sapalla rested the team overnight. By morning their trail was awash in a sea of ice floes.
By the time the team reached Golovin, Togo had covered an amazing 260 miles of the 674 miles between Nenana and Nome. The last Musher in the relay, Gunnar Kaasen, picked up Sappala's second lead dog Balto who had been left behind as a backup at Bluff and completed the last leg of the relay. The serum was delivered, on a trip which normally took twenty-five days, to Dr. Welch in a record time of five days and seven hours after leaving Nenana.
The company that manufactured the serum gave Kassen a $1,000 reward. The press gave full credit to Kaasen and Balto for the miraculous feat, but made no mention of Togo's heroic contribution to the relay. Balto was immortalized in a bronze statue in New York's Central Park, which was dedicated to all sled dogs who ran the 1925 serum relay, and his mounted remains are on display at Cleveland, Ohio's Museum of Natural History.
Seppala felt Togo didn't receive sufficient credit for traveling over the most dangerous and longest part of the relay. The brave 48-pound Siberian Husky was unable to race well after the relay but remained Sappala's lead dog until he was retired at age 16. When Togo died, Seppala had his body mounted and placed it on display at the Iditarod Visitors Center in Wasilla, AK.