Sled dog each year, but after the 1995 events, it was decided to hold them every two years, which facilitated the bidding process and enabled the host organization more time for preparation. Togo was the lead sled dog of Leonhard Seppala and his dog sled team in the 1925 serum run to Nome across central and northern Alaska. Balto was the lead dog of the sled dog team that carried the diphtheria serum on the last leg of the relay to Nome during the 1925 diphtheria epidemic. He was driven by musher Gunnar Kaasen, who worked for Leonhard Seppala. Seppala had also
Iditarod Trail Sled Dog Race of supplies which are flown ahead to each checkpoint by the Iditarod Air Force. The gear includes food for the musher and the dogs, extra booties for the dogs, headlamps for night travel, batteries (for the lamps, music, or radios), tools and sled parts for repairs, and even lightweight sleds for the final dash to Nome. There are three mandatory rests that each team must take during the Iditarod: one 24-hour layover, to be taken at any checkpoint; one eight-hour layover, taken at any checkpoint on the Yukon River; and an eight-hour stop at White Mountain. In 1985, the race