About This Race
The NK50K offers runners a point-to-point tour through Wisconsin's Northern Kettle Moraine Ice Age Trail, celebrating the arrival of spring in what organizers acknowledge will likely be snowy conditions. This community-focused event emphasizes participation over competition, with organizers explicitly noting it's a run, not a race, and no results are posted on UltraSignup. The event maintains a grassroots character with remarkably affordable entry fees and a self-reliant philosophy that encourages runners to be prepared for changing conditions. Both 25K and 50K distances start from different points along the Ice Age Trail system, converging at the Greenbush Group Camp for post-run festivities.
The 50K begins at Ridge Road Trailhead near Sunburst Ski Hill and follows the Ice Age Trail system through the glacially-carved landscape of the Northern Kettle Moraine. The 25K starts later at Crooked Lake, with both distances finishing at Greenbush Group Camp. The course traverses varied terrain typical of the Ice Age Trail, including rolling hills, wooded sections, and open areas shaped by ancient glacial activity. Water is available at backcountry shelters along the route, though runners are advised to be self-sufficient.
Elevation Profile
The course gains 246 ft over 31 miles, with the steepest section between mile 22–mile 22.
Course Map
Route shown is approximate and for illustration purposes.
Aid Stations
3 stations along the course
Mile 3.5 Aid
water, electrolyte, food
For 50K runners only
Mile 25 Aid
water, electrolyte, food
For 50K runners only
Greenbush Group Camp
water, sports drink, cola, mountain dew, food
Finish area with post-race festivities
Practical Info
Early April in Wisconsin typically brings cool temperatures with potential for snow and variable spring conditions.
Best For
Notable Features
The NK50K stands out for its community-focused approach and remarkably affordable entry fee of just $25. Organizers provide shuttle transportation to start lines and emphasize the event's fun-run philosophy with their 'No Whining' policy. The race awards finisher stickers rather than traditional medals, reinforcing its grassroots character and focus on participation over competition.
Prepare for This Race
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A tested guide to the best hydration vests for ultra marathons and long trail races — from lightweight racing vests to high-capacity mountain packs.
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