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Diablo Trails Challenge

Walnut Creek, United States • 4 Apr 2026

Event details

Diablo Trails Challenge takes place on April 4, 2026, at 1700 Castle Rock Road, Walnut Creek, California. The event offers trail race options in multiple distances:

  • 50K
  • Half Marathon
  • 10K
  • 5K

The half marathon is included in the Brazen Ultra Half Series. The race is organized by Brazen Racing and is held on and around Mount Diablo.

Registration, fees and beneficiary

Registration fees vary by distance and increase in phases as the event date approaches. Early listed prices include $159.17 for the 50K, $105.80 for the half marathon, $86.58 for the 10K, $76.98 for the 5K, and a $50.29 remote runner option. A separate BBQ lunch plate ticket is available for $23.60.

A portion of all entry fees will go to Save Mount Diablo. The organization has worked to increase protected open space from 6,788 acres to over 100,000 acres on and around Mount Diablo. 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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