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 both beginners and experienced ultra-runners. The event celebrates and supports the preservation of Mount Diablo's open spaces, with a portion of entry fees benefiting Save Mount Diablo, an organization dedicated to protecting over 100,000 acres of natural land around the mountain. The challenge provides a scenic and rewarding experience on well-maintained trails, promoting outdoor recreation and conservation efforts in the region. Visit the organization's website for the most recent information.

Race information

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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