Diablo Trails Challenge

Walnut Creek, United States • 4 Apr 2026

Diablo Trails Challenge 2026

The Diablo Trails Challenge is an annual trail running event held in Walnut Creek, California. The event base is located at 1700 Castle Rock Road, situated near the trails of Mount Diablo. The race was established to celebrate and support the land preservation efforts of Save Mount Diablo, an organization that has helped expand the open space around the mountain from under 7,000 acres to more than 100,000 acres.

Participants can choose from several distance options:

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

In addition to the in-person races, a Remote Runner option is available for those who wish to participate from a different location. The event contributes a portion of all registration fees to Save Mount Diablo to support the ongoing preservation of local trails and open spaces.

Registered participants and guests have the option to purchase tickets for a BBQ lunch plate provided by Slow Hand BBQ. The event also offers the possibility to transfer registrations, buy registrations as gifts, or participate as a volunteer. The diverse range of distances provides options for individuals new to trail running as well as experienced ultra-runners. Visit the organization's website for the most recent information.

Race information

50 km
50k
Half Marathon
Half Marathon (ultra Half Series)
10 km
10k
5 km
Visit the organization's website for the most recent information.
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