Diablo Trails Challenge
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Diablo Trails Challenge : April 4, 2026
The Diablo Trails Challenge is a trail running event on Mount Diablo in Walnut Creek, California, held on April 4, 2026. It is organized by Brazen Racing and takes place at 1700 Castle Rock Road. The event includes multiple trail race distances and supports the land-conservation group Save Mount Diablo; a portion of entry fees is donated to that organization. The race is part of the Brazen Ultra Half Series, and half marathon runners are invited to participate in the series.
Distances, entry and extras
- 50K
- Half Marathon
- 10K
- 5K
There is also a Remote Runner option and a purchasable BBQ lunch plate. Registration fees are listed with staged price increases; current starting prices shown on the entry page include: 50K $159.17, Half Marathon $105.80, 10K $86.58, 5K $76.98, Remote Runner $50.29, and BBQ plate $23.60. The event provides race information pages for course details, bib pick-up, photos, results, and volunteer opportunities. Visit the organization's website for the most recent information.