Leadville Trail 100 is a 100 miles ultra marathon in Leadville, United States. Distance: 161km. Elevation: 4,800m D+. Difficulty: brutal (Challenge Rating 48/100). DNF rate: 40%. Time limit: 30h. Surface: trail. Established 1983.
Leadville Trail 100
Leadville, Colorado, United States
"The Race Across the Sky. 100 miles through Colorado's highest peaks, never below 2800m."
America's most famous high-altitude 100 miler — an out-and-back at extreme elevation through the Colorado Rockies.
The Course
An out-and-back course through the Colorado Rockies, never dropping below 2800m. The race starts and finishes in Leadville (3094m) and climbs over Hope Pass (3840m) twice. The entire course is at extreme altitude.
mountainous
out-and-back
12
3,840m
Runner Experience
Solid aid station network with 12 stops along the course. Standard ultra fare — food, electrolytes, first aid.
A legendary finish line atmosphere. Leadville Trail 100 is a bucket-list race with celebrations that match its reputation.
Race Day Weather
12°C
-3° – 25°
30%
40%
Extreme altitude weather. Afternoon thunderstorms with lightning are common. Night temperatures well below freezing.
Stats & Records
1983
400
27:00:00
15:42:59
Matt Carpenter (2005)
18:06:24
Ann Trason (1994)
Entry
$350
November
instant
Lore & Trivia
The Leadville Trail 100 began in 1983 to revive a dying Colorado mining town. Ken Chlouber, a miner-turned-mayor, created the race as economic stimulus — ultrarunners would spend money in a town that silver had abandoned. It worked beyond anyone's imagination. Leadville became the most iconic 100-miler in America after Western States, and the race's unofficial motto — "You're tougher than you think you are, and you can do more than you think you can" — became a mantra for the entire sport. The course never drops below 2,800m, crosses Hope Pass twice (3,840m), and the altitude turns the already-brutal distance into a high-altitude survival test that has broken thousands of runners and made legends of the ones who finish.
- ▸ The entire course is above 2800m — even the lowest point is at extreme altitude.
- ▸ Made famous by the book 'Born to Run' which features Leadville as a key setting.
- ▸ The 'Race Across the Sky' nickname refers to the course's extreme altitude throughout.
- ▸ Hope Pass (3840m) is climbed twice — once going out, once coming back. It breaks many runners.
You're tougher than you think you are, and you can do more than you think you can.
Hope Pass at 3am, in the snow, on the way back — that's where Leadville sorts you out.
Notable Editions
The Race That Saved a Town
Ken Chlouber created the Leadville Trail 100 to bring economic activity to a dying mining town. The silver mines had closed, and Leadville was on its knees. The race worked — runners brought money, attention, and eventually a new identity to the highest incorporated city in America.
Born to Run
Christopher McDougall's "Born to Run" featured Leadville prominently, introducing the race to millions of readers worldwide. The book's account of the Tarahumara runners competing at Leadville sparked a global interest in ultrarunning.
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Frequently Asked Questions
How long is Leadville Trail 100? +
Leadville Trail 100 is a 100 miles (161km) ultra marathon with 4,800m of elevation gain. The course is out-and-back on trail terrain.
How hard is Leadville Trail 100? +
Leadville Trail 100 is rated brutal with a Challenge Rating of 48/100 (Challenging). The DNF rate is 40%. Runners have 30 hours to finish.
How do I enter Leadville Trail 100? +
Lottery entry with qualification through Leadville qualifying races or prior 100-mile finish.. Entry is by lottery. Entry costs $350. with a maximum of 800 starters.
What is the weather like at Leadville Trail 100? +
Average temperature is 12°C (range -3°C to 25°C) with 30% humidity and a 40% chance of rain. Extreme altitude weather. Afternoon thunderstorms with lightning are common. Night temperatures well below freezing.
Are crew and pacers allowed at Leadville Trail 100? +
Crew access is allowed. Pacers are allowed after 80km.
What is the course record for Leadville Trail 100? +
The men's course record is 15:42:59 set by Matt Carpenter in 2005. The women's course record is 18:06:24 set by Ann Trason in 1994.
What is the average finish time for Leadville Trail 100? +
The average finish time is 27:00:00. About 400 runners finish each year. The DNF rate is 40%.
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