Diablo Summit Stomp
Walnut Creek, United States • 17 Oct 2026
Event Overview
The Diablo Summit Stomp is a trail race held on October 17, 2026, in Walnut Creek. The event offers several distances run on dirt trails.
Distances and Courses
Participants can choose from one of four courses:
- 30K
- Half Marathon
- 10K
- 5K
All courses start at Castle Rock Park and travel on dirt trails into Mount Diablo State Park. The 30K course goes all the way to the summit of Mount Diablo.
Course Marking and Navigation
The courses are marked with colored ribbons, signs, and flour. Runners are advised to carry a copy of the course map. GPX files for each distance are also available for download to use with navigation apps.
Time Limits and Aid
The 30K race has an overall time limit of 6.5 hours and specific cut-off times at aid stations along the route. 30K runners who reach a specific aid station before a designated time may have the option to switch to the Half Marathon distance mid-race. Half Marathon runners have a cut-off at an aid station approximately 9 miles into the course.
Water stations are provided along the course, stocked with water, sports drink, gels, and snacks. Runners in the 10K, half marathon, and 30K are recommended to carry their own hydration. The event encourages a "cupless" approach, where runners refill their own containers. Visit the organization's website for the most recent information.