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Underdown Trail Races

Merrill, United States • 16 Aug 2025

The Underdown Trail Races, held in Merrill, Wisconsin, offer a challenging trail running experience on the rugged Underdown Trail system shaped by ancient glaciers. The event features distances of 60k, marathon, and half marathon, with courses primarily on singletrack trails that include steep climbs and dozens of boardwalks passing isolated lakes. Known for its wilderness atmosphere, the race emphasizes physical and mental endurance in remote terrain with limited cell service. Participants enjoy well-marked courses, stocked aid stations, and a festive after-party with live music, food, and awards. Proceeds support trail building and maintenance, ensuring a grassroots, intimate trail running event since 1989. Visit the organization's website for the most recent information.

United States Wisconsin Merrill

Race information

Website
60 km
60k
26 mi
Marathon
13 mi
Half Marathon
Visit the organization's website for the most recent information.
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