Frozen 4 Hour & 5K - Duluth Winter Trail Series
Woodlands/Pleasantview, United States • 7 Feb 2026
Frozen 4 Hour & 5K - Duluth Winter Trail Series
The Frozen 4 Hour is a timed four hour trail running event held on packed, snowpacked multi-use fat bike trails in Lester Park, Duluth, Minnesota. Competitors attempt to run as many miles as possible within the four hour time limit on a primarily 5K loop that serves as the course. A 5K option is offered for participants who prefer to run a single lap.
The event is part of the Duluth Winter Trailrunning Series, a sequence of winter races that use packed fat bike trails around Duluth. The series includes several races at different parks and offers a special award to runners who complete all four races. Some races in the series include snowshoe and no shoe trail running divisions.
Course features include packed multi-use trails in Lester Park and a looped 5K that is used repeatedly for the timed format. The race describes the trail surface as frozen and snowpacked and situates the start and finish in the Lester Park area at the Lester-Amity Chalet. The format emphasizes lap running on a consistent loop to measure distance covered during the four hour period. Visit the organization's website for the most recent information.