Lean Horse 100 Mile
Lean Horse 100 Mile follows the George S. Mickelson Trail through South Dakota's Black Hills on a runnable crushed-limestone rail-trail route.
Every link above goes to the race, its timing provider, or an official registration partner. Last checked July 23, 2026.
Quick facts
- Saturday start on August 1, 2026
- 100 miles on the Mickelson Trail
- Runnable rail-trail profile
- Black Hills setting
2026 Lean Horse 100 Mile registration
Registration for the 2026 Lean Horse 100 Mile runs through the official registration page at raceroster.com.
About the Lean Horse 100 Mile
The event offers a separately entered and timed 100-mile distance, supported by a long-running ultra organization and an established finish history.
Course
The Mickelson Trail supplies gentle rail-trail grades, tunnels and Black Hills scenery, making sustained running efficiency more important than technical skill.
Race-day weather
Early August may be hot and sunny in open sections, while the night can cool sharply; thunderstorms and altitude add uncertainty.
Past Lean Horse 100 Mile dates and results
| Year | Date | Status | Results |
|---|---|---|---|
| 2026 | Saturday, August 1, 2026 | Upcoming | — |
Lean Horse 100 Mile FAQ
When is the Lean Horse 100 Mile?
The 2026 Lean Horse 100 Mile is on Saturday, August 1, 2026.
How do I register for the Lean Horse 100 Mile?
Register for the Lean Horse 100 Mile through the official registration link: marathonscout.com/go/lean-horse-100-mile/register. It opens the race registration page at raceroster.com.
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