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 multiple mountain biking options. The course features challenging singletrack trails with significant elevation changes and scenic views of isolated lakes, enhanced by numerous boardwalks. The event emphasizes a wilderness experience, with proceeds supporting trail maintenance. Finishers receive custom awards, and the event includes an after-party with live music, food, and refreshments. 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
13 mi
13 Mile
13 mi
Half Marathon
Visit the organization's website for the most recent information.
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