Ultramarathon

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.

Next race2027 date TBD
Distance categoryUltramarathon
LocationCuster, South Dakota
Get alertsLast checked August 4, 2026

Quick facts

  • Saturday start on August 1, 2026
  • 100 miles on the Mickelson Trail
  • Runnable rail-trail profile
  • Black Hills setting

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

YearDateStatusResults
2026Friday, July 31, 2026CompletedOpen results

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Lean Horse 100 Mile FAQ

When is the Lean Horse 100 Mile?

We're waiting for the finalized date for the 2027 Lean Horse 100 Mile. The most recent running was on Friday, July 31, 2026.

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