Leadville Trail 100 Run
The Race Across the Sky -- 100 miles at altitude through the Colorado Rockies.
Leadville, Colorado
Mid-August
161 km
4,800 m
~800 athletes
Course Highlights
- Leadville start at 10,200 feet elevation
- Hope Pass at 12,620 feet (crossed four times)
- Twin Lakes turnaround area
- Winfield ghost town at mile 50
- Aspen groves and high-altitude forests
- Views of the Sawatch Range
The Course
The Leadville Trail 100 begins on the streets of Leadville, Colorado, at an elevation of 10,200 feet, making it the highest city in North America. The out-and-back course heads south through the historic mining town before entering the forested trails and dirt roads of the surrounding Sawatch Range.
The defining feature of the course is Hope Pass, which runners must cross twice in each direction (four times total). The climb to Hope Pass reaches 12,620 feet, where the thin air makes every step a battle. The pass features steep, exposed switchbacks above treeline with stunning views of the Twin Lakes valley below. Between the high passes, the course traverses a mix of dirt roads, jeep trails, and single-track through aspen groves and evergreen forests.
The turnaround at Winfield, a ghost-town mining camp at mile 50, marks the halfway point. From there, runners retrace their steps back over Hope Pass and through the identical terrain to Leadville. The altitude is the race's primary challenge; even well-trained runners find their pace significantly reduced above 10,000 feet. The 30-hour cutoff and the large silver belt buckle for sub-25-hour finishers add to the race's legendary status.
History
The Leadville Trail 100 was founded in 1983 by Ken Chlouber as an economic stimulus for the struggling mining town of Leadville, Colorado. The race quickly became one of the most iconic ultramarathons in the world, known for its extreme altitude and the gritty determination it demands.
The race gained wider fame through the book "Born to Run" by Christopher McDougall and the documentary "Race Across the Sky." The large silver belt buckle awarded to sub-25-hour finishers is one of the most recognized prizes in ultrarunning.
How to Train for Leadville 100
Altitude acclimation is non-negotiable
The entire race takes place above 9,200 feet, with sections above 12,000 feet. Arrive at altitude at least two weeks before the race, or consider a live-high-train-low protocol. Altitude sickness can end your race before it starts.
Train for the out-and-back mentally
Running back over the same terrain you just covered, including Hope Pass a second time, is a unique mental challenge. Practice mental strategies for out-and-back courses and prepare for the psychological difficulty of knowing exactly what lies ahead.
Practice power hiking at altitude
Above 11,000 feet, most runners resort to power hiking on climbs. Make power hiking a deliberate part of your training, including using trekking poles. Efficient hiking can be faster than shuffling at altitude.
Qualification
Runners must complete a qualifying ultramarathon to enter the lottery. Qualifying races and distances vary; check the Leadville Race Series website for current requirements.
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