Lean Horse Ultra
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About the race
The Lean Horse Ultra Marathon on July 30–31, 2027 is an ultramarathon event held in Custer, South Dakota, on the George S. Mickelson Trail. The course surface is crushed limestone and follows an old railroad bed, producing extended gentle climbs rather than steep technical sections. The event lists multiple race formats and a CrossFit edition held on the same trail.
Distances offered:
- 100-mile race
- 100-mile relay
- 50-mile race
- 30-mile race
- 20-mile race
- 30-mile Black Hills CrossFit Edition, singles and 3- and 6-person relays
Registration opens October 1 and closes July 16. Pricing is tiered by date: early bird, standard, and last minute periods are shown with specific fees for each distance. Example fees include early bird pricing for the 100-mile at $375 and for the 50-mile at $180; standard and last minute prices increase on the dates provided.
The event is staged in the town of Custer in the Black Hills region. Average August daytime temperatures for the area are listed as a high of 79 degrees and a low of 53 degrees. The Lean Horse Ultra Marathon is noted as the 33rd sanctioned 100-mile race in the United States. Visit the organization's website for the most recent information.
