Diablo Trail Run

Diablo Trail Run : Sun September 6, 2026, Clayton, CA

The event is held at Diablo State Park (Mitchell Canyon Trailhead) in Clayton, CA. Distances offered on race day include:

• 4 Mi
• 10 Mi
• Half Marathon
• Marathon
• 50K
• Kid's Run (6 years and younger, 50 yd dash; free)
• Coastal Testing

Course and race logistics

The venue is on Mount Diablo, which overlooks the San Francisco Bay Area and surrounding valleys. The 4 mile course runs mostly within Mitchell Canyon and is described as relatively flat. Longer distances follow mountainous trail and dirt-road sections. Course markings include ribbon approximately every 200 yards, color coding by distance, and polka-dot flagging to indicate turns; blue ribbons mark wrong-way junctions. Elevation gain and surface mix by distance are provided for each course (examples: 4 mi gain 400 ft; 50K gain 8,000 ft). Single-track, dirt road, and asphalt percentages vary by distance.

Aid stations are fully stocked every 3 to 5 miles with fresh fruit, salty snacks, candy, water, and Skratch electrolyte drink; runners are advised to carry at least 20 oz of water between stations. The event is cupless - participants should bring their own fluid container; Hydrapak SpeedCups are available for purchase at check-in. Bib timing uses MyLaps Bibtags and results are published during the event. Parking is $6 per vehicle. Shirts are guaranteed for registrations completed at least 10 business days before the event. No dogs are allowed on course. Visit the organization's website for the most recent information.