California · 12 Miler
Mountain Tiger Diablo
Mountain Tiger Diablo is a 12 Miler event held in Clayton, California. It was last held on October 10, 2026 and is usually run in October; the next date hasn't been announced yet. About 400 runners take part across all distances.
- Usually held
- October
- Location
- Clayton, CA
- Field size
- ~400 runners
Race details
- Last held
- October 10, 2026
- Usually held in
- October
- Location
- Clayton, California
- Distances
- 12 Miler
- Field size
- About 400 runners
- Course
- Very hilly mountain course: approximately 4,000 ft of climbing and 4,000 ft of descent over 12.4 miles, per official course page.
- Registration
- ultrasignup.com
- Official website
- mountaintiger.com
Registration, course & weather
- Registration status
- Registration status as last checked September 28, 2026: open
- Start time
- 7:00 AM PDT
- Course profile
- Loop course; Mostly trail, some road; 4000 ft gain, 4000 ft loss (official course data)
About the Mountain Tiger Diablo
Mountain Tiger Diablo is a new 12.4-mile mountain race, launching in October 2026, that starts and finishes at the Mitchell Canyon Visitor Center in Clayton and climbs directly to the summit of Mount Diablo via Eagle Peak and Bald Ridge Trail before a steep descent back down. Organized by Connor and Alice Curley of Mountain Tiger, it follows their debut Donner Summit race and features a group shuttle, post-race raffle, and unique finisher item.
More races in Clayton
More upcoming races in California
-
Dia De Los Muertos Half Marathon & 5K Run/Walk (Bakersfield)Bakersfield, CAHalf Marathon5K2 Mile Speed Walk
Keep exploring
- All races in California
- 5Ks in California 459 upcoming races
- 10Ks in California 316 upcoming races
- Half Marathons in California 197 upcoming races
- Marathons in California 41 upcoming races
- October races in California
- Races in Arizona 172 upcoming races
- Races in Oregon 92 upcoming races
- Races in Nevada 71 upcoming races
Guides from the RaceRove blog
- 8 min read How to Choose the Best Half Marathon for a PR, Racecation or 50-State Challenge The best half marathon depends on what you want from it. How to choose a course for a personal record, a race worth travelling for, or an efficient stop on a 50-state challenge.
- 4 min read Diplo's Run Club 2026-27: Every City, Date and Course Diplo's Run Club is a 5K with a post-race concert. Every US date for 2026-27 (San Francisco, New York, Los Angeles, San Diego and Phoenix), start times and courses.
- 8 min read How to Choose Your First Marathon A practical checklist for choosing a first marathon based on course, weather, cutoff, travel, field size and support.
- Blog All guides Planning advice for finding, choosing and travelling to races.
Mountain Tiger Diablo: common questions
- When is the Mountain Tiger Diablo?
- The next date hasn't been announced in the listing yet. The race is usually held in October. Check the organiser's website for the official date.
- Where is the Mountain Tiger Diablo held?
- In Clayton, California.
- What distances does the Mountain Tiger Diablo offer?
- 12 Miler.
- How many people run the Mountain Tiger Diablo?
- About 400 runners across all of its distances. That figure is an estimate of the field size, not an entry cap.
- How do I register for the Mountain Tiger Diablo?
- Registration is handled by the organiser at ultrasignup.com. Entry fees, caps and deadlines are set there.
- Is registration open for the Mountain Tiger Diablo?
- Registration status as last checked September 28, 2026: open. $105 (from mountaintiger.com, checked September 28, 2026).
- What time does the Mountain Tiger Diablo start?
- 7:00 AM PDT.
- What is the course like at the Mountain Tiger Diablo?
- Loop course; Mostly trail, some road; 4000 ft gain, 4000 ft loss (official course data).
Plan this race in RaceRove
Save it to your plan, compare it with other races, check typical race-day weather and track your 50-state progress in the interactive app.