Ouray 100 Mile Endurance Run
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About the race
The Ouray 100 Mile Endurance Run is a one-hundred mile trail race in Ouray, Colorado, centered at Fellin Park in the San Juan Mountains. The course totals 41,862 feet of elevation gain and includes fourteen climbs, with a final roughly 5,000 foot ascent to the Bridge of Heaven followed by a descent to Fellin Park and the Ouray Hot Springs. The event awards a special belt buckle to finishers. Each participant must complete eight hours of volunteer service before July 1 or pay a $100 opt out donation to the Ouray Trail Group.
Entrants who have not submitted a service form or paid the opt out fee by July 10 will forfeit their registration and will not be permitted to participate. The service form is available on the event website. The race is not a UTMB qualifier. Live tracking is required: runners must carry a SPOT tracker provided by the organizers, with location updates every five minutes.
Top finishers are subject to urine and/or blood drug testing immediately after the event; banned substances include, but are not limited to, steroids, testosterone, EPO, and THC. THC levels above 150 ng/ml may trigger a positive result. Cash awards are listed for top finishers, with amounts subject to testing results. Packet pickup and a pre-race talk take place at Fellin Park the day before the race.
Registration opens December 5, 2026 and the event takes place on July 16, 2027. Visit the organization's website for the most recent information.
