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Course Highlights
The Leadville Trail 100 Run — the Race Across the Sky — is the defining event of American ultrarunning. The 99.7-mile out-and-back course starts and finishes in Leadville, Colorado (10,152 feet, the highest incorporated city in the United States) and crosses the legendary Hope Pass twice at 12,500–12,600 feet, climbs the rugged Powerline section, traverses technical stretches of the Colorado Trail, and descends to the lowest point of 9,200 feet at Twin Lakes. The course accumulates 15,492 feet of elevation gain across its full length, with 11 aid stations to sustain runners through the mountains.
Race Details
The 2026 race starts August 22 at 4:00 AM from the corner of 6th and Harrison in Leadville. The starting line opens at 3:00 AM. Pacers are allowed after mile 61.8 (Twin Lakes inbound). The official 30-hour cutoff earns finishers the coveted small silver belt buckle; completing the course in under 25 hours earns the Big Buckle — a trophy that defines careers. Minimum age is 18 on race day. The race is managed by the Leadville Race Series and typically sells out within minutes of registration opening.
Why Runners Love It
The Leadville 100 launched the modern ultrarunning movement when it was founded in 1983, and it remains the aspirational pinnacle for hundreds of thousands of runners worldwide. The combination of extreme altitude, rugged terrain, remote mountain wilderness, and the simple binary outcome — finish or DNF — gives the race a gravity and mystique unmatched in American endurance sports. The Hope Pass double-crossing in the dark of night is one of the most profound experiences available in trail running.
Race Weekend Tips
Training at altitude is almost impossible to replace with sea-level preparation. If you live below 5,000 feet, plan to arrive in Leadville at minimum one week before race day — preferably two. The average pace needed just to finish (30 hours) is approximately 18 min/mile including all stops, which sounds easy until you’re above 12,000 feet at mile 50 after midnight. Crew and pacers are essential, and a meticulously prepared drop bag system across the 11 aid stations is the difference between finishing and not.
Register
Registration opens in January via the Leadville Race Series at leadvilleraceseries.com. Spots sell out in minutes — set a calendar reminder and have your payment information ready before registration opens.
Leadville, Colorado United States
Course Highlights
The Leadville Trail 100 Run — the Race Across the Sky — is the defining event of American ultrarunning. The 99.7-mile out-and-back course starts and finishes in Leadville, Colorado (10,152 feet, the highest incorporated city in the United States) and crosses the legendary Hope Pass twice at 12,500–12,600 feet, climbs the rugged Powerline section, traverses technical stretches of the Colorado Trail, and descends to the lowest point of 9,200 feet at Twin Lakes. The course accumulates 15,492 feet of elevation gain across its full length, with 11 aid stations to sustain runners through the mountains.
Race Details
The 2026 race starts August 22 at 4:00 AM from the corner of 6th and Harrison in Leadville. The starting line opens at 3:00 AM. Pacers are allowed after mile 61.8 (Twin Lakes inbound). The official 30-hour cutoff earns finishers the coveted small silver belt buckle; completing the course in under 25 hours earns the Big Buckle — a trophy that defines careers. Minimum age is 18 on race day. The race is managed by the Leadville Race Series and typically sells out within minutes of registration opening.
Why Runners Love It
The Leadville 100 launched the modern ultrarunning movement when it was founded in 1983, and it remains the aspirational pinnacle for hundreds of thousands of runners worldwide. The combination of extreme altitude, rugged terrain, remote mountain wilderness, and the simple binary outcome — finish or DNF — gives the race a gravity and mystique unmatched in American endurance sports. The Hope Pass double-crossing in the dark of night is one of the most profound experiences available in trail running.
Race Weekend Tips
Training at altitude is almost impossible to replace with sea-level preparation. If you live below 5,000 feet, plan to arrive in Leadville at minimum one week before race day — preferably two. The average pace needed just to finish (30 hours) is approximately 18 min/mile including all stops, which sounds easy until you’re above 12,000 feet at mile 50 after midnight. Crew and pacers are essential, and a meticulously prepared drop bag system across the 11 aid stations is the difference between finishing and not.
Register
Registration opens in January via the Leadville Race Series at leadvilleraceseries.com. Spots sell out in minutes — set a calendar reminder and have your payment information ready before registration opens.