Underdown Trail Races

Merrill, United States • 16 Aug 2025

The Underdown Trail Races, organized by IRONBULL, are grassroots trail running and mountain biking events held in Northern Wisconsin. Scheduled for August 16, 2025, participants can choose from various distances, including a 60k, marathon, and half marathon for runners, as well as mountain bike races of 111 miles, 37 miles, and 16 miles. The challenging course features singletrack trails, numerous hills, and scenic views of isolated lakes, making it a true wilderness experience. The event emphasizes community and sustainability, with proceeds supporting trail maintenance and an after-race celebration featuring food, music, and awards. Visit the organization's website for the most recent information.

Race information

111 mi
111 Mile
60 km
60k
37 mi
37 Mile
26 mi
Marathon
16 mi
16 Mile
13 mi
Half Marathon
Visit the organization's website for the most recent information.
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