Rocky Mountain Slam
Logan, United States • 25 Sep 2026
Rocky Mountain Slam
The Rocky Mountain Slam is a series of ultramarathons in the Mountain West region of the United States. The concept originated in the early 2000s as an addition to other established race series.
Series Format
To complete the Slam, a runner must finish a total of four 100-mile races. The Bear 100 is the only mandatory event, as it is the final race of the series. Runners choose the remaining three races from a list of nine optional 100-mile events.
History and Changes
The original series format required specific races. Due to increasing difficulty in gaining entry via lotteries for some events, the series was revised (V2.0). This new format, announced in 2022, expanded the optional race list to increase accessibility. Races are spread across the months from June to September.
Included Races (Optional)
Runners can select from:
- Scout Mountain 100
- Bighorn 100
- Hardrock 100
- Leadville 100
- Wasatch Front 100
- Ouray 100
- Wyoming Range 100
- High Lonesome 100
- Crazy Mountain 100
A separate registration for the Rocky Mountain Slam series itself is required to cover organizational costs and to provide an award for finishers. Visit the organization's website for the most recent information.