Muir Woods Mountain Challenge
Stinson Beach, United States • 18 Jul 2026
Muir Woods Mountain Challenge
The Muir Woods Mountain Challenge is a trail race series held at Mt. Tamalpais State Park near Stinson Beach, CA. The event offers three distances:
- 10K (6.4 miles, 1,950' elevation gain)
- Half Marathon (13.1 miles, 3,450' elevation gain)
- 30K (18.8 miles, 4,950' elevation gain)
Courses start with a steep climb of about 2,000 feet in just over 2 miles on Willow Camp hill, then follow ridge-line single-track with views of Stinson Beach and the Pacific Ocean. The 10K returns to the beach via the Matt Davis Trail. The Half and 30K continue up Mt. Tam along the Dipsea Trail and pass through Muir Woods before descending back to Stinson Beach on the Dipsea Trail, which includes steep steps. Trail surfaces are primarily technical dirt trails and fire roads with long climbs, rocky and rooty descents, steps, and many turns. Hiking poles are permitted.
Courses are marked with colored ribbon roughly every 200 meters; blue ribbons indicate wrong-way trails. Aid stations supply a range of energy foods and drinks and basic first aid items; disposable cups are not provided. The event is chip timed with disposable chips attached to bibs. Capacity is limited to 300 runners across all distances. Parking is available within the Stinson Beach Day Use Area and is free of charge. Visit the organization's website for the most recent information.