Ouray 100 Mile Endurance Run
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Ouray 100 Mile Endurance Run : July 17, 2026
The event is a 100 mile mountain ultramarathon held in Ouray, Colorado, with start and finish at Fellin Park. The course includes about 41,862 feet of elevation gain and fourteen significant climbs, including a final roughly 5,000-foot ascent to a high point called the Bridge of Heaven before descending back to Fellin Park. The race has a 52-hour cutoff for the 100-mile distance. Finishers receive a belt-buckle award; the finish area is near the Ouray Hot Springs.
Entry, rules, and race services
Registration opens on December 6, 2025. Each participant must complete eight hours of volunteer service before July 1 or pay a $100 opt-out donation; entrants who have not submitted proof of service or paid the opt-out by July 10 will forfeit their registration. The event is no longer a UTMB qualifier. Top finishers receive cash prizes subject to drug testing: $1,000 for the top male and $1,250 for the top female 100-mile finisher. Winners may be required to provide urine and/or blood samples; testing may cover steroids, testosterone, EPO, and THC (the THC threshold for a positive result is 150 ng/ml). Runners must carry a provided SPOT tracker during the race; locations will update every five minutes. Packet pickup and a pre-race briefing are scheduled at Fellin Park the day before the race. Visit the organization's website for the most recent information.