Lean Horse Ultra Marathon

The Lean Horse Ultra Marathon, celebrating its 34th edition since its inception in 2005, invites runners to explore the breathtaking landscapes of South Dakota's Black Hills. This annual event takes place every August on the historic George S. Mickelson Trail, a converted railroad line that offers a unique and challenging course experience.
The trail surface is composed of crushed limestone, providing a smooth yet rugged terrain for participants. The elevation profile features extended gentle climbs, adding to the physical challenge while maintaining an overall manageable route. This makes it one of the best non-technical courses in the United States, ideal for both seasoned ultra-runners and those looking to push their limits.
Spanning distances from 20 miles up to a grueling 100-mile race, runners can choose between individual races or participate in exciting relays such as Singles, Triplets, and Six-person teams. The event’s hosting town, Custer, South Dakota, offers a charming backdrop with its rich history and natural beauty.
The weather during the race is typically mild, with average daytime highs reaching 79 degrees Fahrenheit and lows dropping to 53 degrees. This comfortable climate ensures that runners can focus on their performance without dealing with extreme conditions.
What sets The Lean Horse Ultra Marathon apart are its stunning scenic views of the Black Hills. Known for being one of the most picturesque rail-to-trail courses in the country, this race promises an unforgettable experience filled with natural wonders and breathtaking vistas.
Whether you're a seasoned ultra-runner or just looking to challenge yourself in a beautiful setting, The Lean Horse Ultra Marathon is poised to offer an extraordinary adventure through South Dakota's scenic Black Hills.