O'brien Trail Races

O'Brien Trail Races are held at William O'Brien State Park, near Marine on Saint Croix, Minnesota. The event offers four distances: 50K, 25K, 10K, and 5K. The premier 50K course runs two 25K loops through the park’s upper and south sections and Jackson Meadows, with four aid stations per loop and a nine-hour time limit.

The 5K and 10K are wide grass-trail courses featuring one large hill, with no aid stations, no awards, but a finish-print for all finishers. A family-friendly atmosphere, park setting, optional race shirts, and post-race refreshments round out the experience. Visit the organization's website for the most recent information.