The trail is composed of two routes: a northern route, which is run on even-numbered years, and a southern route, which is run on odd-numbered years. Both follow the same trail , from Anchorage to Ophir, where they diverge and then rejoin at Kaltag, from Nome. The race used the northern route until 1977, when the southern route was added to distribute the impact of the event on the small villages in the area, none of which have more than a few hundred inhabitants. Passing through the historic town of Iditarod was a secondary benefit.
The trail is composed of two routes: a northern route, which is run on even-numbered years, and a southern route, which is run on odd-numbered years. Both follow the same trail , from Anchorage to Ophir, where they diverge and then rejoin at Kaltag, from Nome. The race used the northern route until 1977, when the southern route was added to distribute the impact of the event on the small villages in the area, none of which have more than a few hundred inhabitants. Passing through the historic town of Iditarod was a secondary benefit.