Mount Disappointment Mountain Race
Mount Wilson, United States • 26 Sep 2026
Trail Running in the Angeles National Forest
The Mount Disappointment Mountain Race takes place in the Angeles National Forest, California. The event begins and ends at Skyline Park at the summit of Mt. Wilson, located approximately 45 minutes from Los Angeles. Participants navigate historical mountain terrain including technical single track, rocky sections, steep climbs, and fast descents through pine forests and chaparral.
The course is 95% single track and reaches a peak elevation of 5,800 feet. Notable landmarks along the route include the Mt. Wilson Observatory, a historic Nike missile site, and panoramic views of the San Gabriel Valley. The race offers two distinct distances:
- 50K Ultra: A 31-mile course with 7,000 feet of elevation gain and a 10-hour cutoff time.
- 25K Challenge: A 15.5-mile course with 3,800 feet of elevation gain and a 5-hour cutoff time.
The trails are marked with ribbons and signs. Fully stocked aid stations are positioned every 5 to 7 miles, though runners are encouraged to carry extra water between Josephine Saddle and Red Box. Athletes in the 50K receive five aid stations, while 25K runners have access to two.
Course rules prohibit pacers and drop bags at aid stations. Trekking poles are permitted and recommended, and it is highly suggested that participants carry GPS tracks. Awards are presented to the top three male and female finishers in each distance. All participants receive a finisher medal and tech race shirt, with an additional buckle provided to 50K finishers.
The event utilizes the Mt. Wilson Observatory parking lot, which requires a displayed Adventure Pass. Crew access is restricted to the start/finish area and the Red Box Picnic Area. Visit the organization's website for the most recent information.