Muir Woods Mountain Challenge

Muir Woods Mountain Challenge

This trail running event in Mt. Tamalpais State Park, Stinson Beach, CA, on July 18, 2026, offers three measured distances and marked, chip-timed courses. Distances and official elevation figures are listed below.

• 10K - 6.4 miles, 1,950 ft elevation gain
• Half Marathon - 13.1 miles, 3,450 ft elevation gain
• 30K - 18.8 miles, 4,950 ft elevation gain

The courses start with a steep climb up Willow Camp hill that gains about 2,000 ft in just over 2 miles. Runners follow coastal ridge single-track with views of Stinson Beach and the Pacific, descend the Matt Davis Trail to the beach for the 10K, and for the Half and 30K continue up the Dipsea Trail through Muir Woods to the Cardiac Hill summit before returning to Stinson Beach via the Dipsea Trail. Terrain is mainly technical dirt trails and fire roads with long climbs, rocky and rooty descents, steps, and tight turns. Trekking poles are permitted.

Courses are marked with colored ribbon approximately every 200 meters; blue ribbons mark wrong-way trails. Aid stations supply energy gels, snacks, drinks, and basic first aid; runners are encouraged to carry at least one 20 oz bottle. The event is cupless, so runners must carry their own cup or flask. Capacity is 300 entrants across all distances. Timing is by disposable chip attached to the back of each bib. There is a 6.5 hour time limit for the Half and 30K; all runners must be off course by 2:00 PM. Awards include overall trophies by gun time, age-group awards by chip time, and finisher medals. Visit the organization's website for the most recent information.