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.

Race information

60 km
60k
Marathon
Marathon
Half Marathon
Half Marathon
Visit the organization's website for the most recent information.
Trail runs nearby

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Ragnar Trail Wisconsin is a team relay across scenic single track trails in Nine Mile Forest near Wausau. Camp in Ragnar Village and enjoy bonfires, music, yoga and festival style camaraderie between loops.