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Diablo Trails Challenge

Walnut Creek, United States • 4 Apr 2026

The Diablo Trails Challenge is a trail running event held at 1700 Castle Rock Road, Walnut Creek, California. It offers multiple race distances including a 50K ultra, half marathon, 10K, and 5K, catering to runners of all experience levels from beginners to seasoned ultra-runners. The event supports Save Mount Diablo, an organization dedicated to preserving and expanding open space around Mount Diablo, with a portion of entry fees donated to their cause. The challenge celebrates over 40 years of conservation efforts and provides participants the opportunity to enjoy scenic trails while contributing to environmental preservation. Visit the organization's website for the most recent information.

United States California Walnut Creek

Race information

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