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Diablo Trails Challenge

Walnut Creek, United States • 4 Apr 2026

Diablo Trails Challenge is a trail-running event held at 1700 Castle Rock Road, Walnut Creek, CA, in support of Save Mount Diablo. The race offers multiple distances to suit all levels: 50K, half marathon, 10K, and 5K, plus a Remote Runner option. The course traverses Mount Diablo’s open-space trails, appealing to both first-time trail runners and seasoned ultramarathoners. A portion of each entry fee benefits Save Mount Diablo to help preserve and expand the region’s open space and trails. The event celebrates trail achievements and community involvement, with extras such as a BBQ lunch option for participants. Visit the organization's website for the most recent information.

United States California Walnut Creek

Race information

Website Registration
50 km
50k
21 km
Half Marathon
10 km
10k
5 km
Remote Runner
Visit the organization's website for the most recent information.
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