Ouray 100 Mile Endurance Run

Ouray, United States • 18-20 Jul 2025

The Ouray 100 Mile Endurance Run is a challenging ultramarathon set in the breathtaking San Juan Mountain range of Colorado. Participants face approximately 41,862 feet of elevation gain over the course of the race, making it one of the toughest endurance events. Runners must complete eight hours of volunteer service before the event or opt out by donating to the Ouray Trail Group. The race features a cash purse for top finishers, with drug testing conducted post-race. The event emphasizes a no-frills, old-school approach, rewarding those who conquer the course with a unique belt buckle and a sense of accomplishment. Visit the organization's website for the most recent information.

Race information

100 mi
41862 m+
100 Mile
Visit the organization's website for the most recent information.
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