A winter endurance challenge through Alaska’s frozen backcountry
Overview
The Susitna 100 is a rugged winter ultramarathon set in the Susitna River Valley north of Anchorage, Alaska. Participants may complete the 100-mile course by foot, bike, or ski. With no outside support beyond checkpoints, racers must carry mandatory survival gear and navigate snowmachine and dogsled trails under often extreme and unpredictable conditions. This is a true test of endurance, resilience, and self-reliance.
Entry Requirements
Must pass gear check; winter endurance experience strongly recommended
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