Leadville Trail 100 Mile Run

Leadville, United States • 16-17 Aug 2025

The Leadville Trail 100 Mile Run, held annually in Leadville, Colorado, is a legendary ultramarathon known as the "Race Across the Sky." Established in 1983, this grueling 100-mile out-and-back course challenges runners with extreme Rocky Mountain terrain, starting at 10,200 feet and reaching a peak elevation of 12,600 feet at Hope Pass. The course features over 15,700 feet of elevation gain, including steep climbs and technical trails through the Colorado Rockies. With 11 aid stations and strict cutoff times, the race tests endurance, grit, and determination. Finishers under 30 hours earn a coveted belt buckle, making it a prestigious event in the ultrarunning community. Visit the organization's website for the most recent information.

Race information

100 mi
15744 m+
100 Miles
Visit the organization's website for the most recent information.
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