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 climbing to a peak elevation of 12,600 feet at Hope Pass. The route features rugged forest trails, steep climbs, and over 15,700 feet of elevation gain. 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 one of the most iconic and demanding endurance events worldwide. 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.
Trail runs nearby

The Leadville Trail Marathon and Heavy Half are challenging trail running events held in Leadville, Colorado, featuring rugged courses through the historic mining district. The marathon covers 26.4 miles with an elevation gain of 6,167 feet, reaching the highest point at Mosquito Pass at 13,185 feet..

The Leadville Firecracker 5K is a festive running event held in Leadville, Colorado, the highest incorporated city in North America. Participants can walk or run a 5-kilometer (3.1-mile) course that begins and ends in downtown Leadville, offering a unique high-altitude experience above 10,000 feet...

The Silverheels Trail Runs, hosted by the Human Potential Running Series, is a premier ultra running event held in Como, Colorado, at an average elevation above 10,000 feet. The event features multiple distances including 10-Mile, 19-Mile, 60k, 50-Mile, 100k, and 100-Mile races, with the 100-Mile an..

The Leadville Silver Rush 50M is a challenging 50-mile trail run held in Leadville, Colorado, featuring 7,503 feet of elevation gain and reaching a high point of 12,024 feet. The out-and-back course traverses historic mining roads on the east side of Leadville, offering runners stunning views of the..

The Audi Power of Four Trail Run is a scenic trail running event held in Aspen, Colorado, featuring routes across the mountains of Aspen Snowmass. Scheduled for July 19, 2025, the race offers three distance options: 50K, 25K, and 10K, catering to a range of trail runners. Participants experience div..

The Summit 200 is a challenging 200-mile mountain ultramarathon held in Summit County, Colorado. The race features a single large loop primarily on stunning hiking trails, forest roads, recreation paths, and some pavement, with elevations ranging from over 9,000 feet to nearly 13,000 feet. Participa..