Diablo Trail Run
When is Diablo Trail Run?
Diablo Trail Run takes place on Sunday, September 6, 2026 in Clayton, CA.
What distances does Diablo Trail Run offer?
Diablo Trail Run offers 5 events: 4 Mi, 10 Mi, Half Marathon, Marathon, 50K.
| Event | Distance | Price | |
|---|---|---|---|
| 4 Mi | 4.0 mi | $50.00 | Register |
| 10 Mi | 10.0 mi | $60.00 | Register |
| Half Marathon | 13.1 mi | $70.00 | Register |
| Marathon | 26.2 mi | $80.00 | Register |
| 50K | 30.4 mi | $90.00 | Register |
How much does Diablo Trail Run cost?
Registration for Diablo Trail Run starts at $100.00. Prices vary by event distance.
Where is Diablo Trail Run held?
Diablo Trail Run is held in Clayton, CA at Diablo State Park (Mitchell Canyon Trailhead).
About Diablo Trail Run
Mount Diablo provides spectacular views of the San Francisco Bay Area and surrounding valleys. The 4 mile course is relatively flat and fast within Mitchell Canyon. The longer events are mountainous and very scenic.
(Distances are accurately measured using a Rolatape® surveyor's measuring wheel.)
Cancellation Policy
Entry fees to Coastal events are non-refundable.
DEFER YOUR ENTRY
To defer an event that is scheduled as planned:
Things happen or you change your mind. If you're just not able to make the event that you had planned on, here are your options:
- Up until 7 days from the start time of the first event, you can defer 100% value of your registration to a future event for a deferment fee of $10. You will be given a credit for the amount paid, minus any discounts and service fees, to be used at a future event.
- Up until 72-hours from the start time of the first event, you will be given a credit for 50% of the amount paid towards a future event, minus any discounts and service fees, to be used at a future event.
- Up until 72-hours from the start time of the first event, you can transfer your registration of the current event to another runner for a transfer fee of $10.
Please use the Contact this Race form and notify us within the time frame stated above.
All requests within 72-hour from the start time of the first event will not earn credit nor be eligible for a transfer.
All race credits earned will be good for one calendar year from the time it was issued.
EVENT CANCELLATIONS
We host events rain or shine but in the unfortunate circumstance that an event is:
- canceled or rescheduled - you will receive a 75% credit of your registration fee (minus processing and other fees incurred), applicable to future events
- relocated - we will automatically transfer the registration over to new venue.
Bib Number & Shirt Pick-up
Race Day: Check-in beginning at 7:00 a.m. at Mt. Diablo State Park (Mitchell Canyon Trailhead). Please arrive 45min before your event to receive your bib and shirt. Event start times are listed here.
Parking is $6 per vehicle. Please bring exact change to expedite entry.
No Bag Check: You can leave non-valuables at the Start/Finish.
Shirts
To guarantee a shirt, please register 10 business days prior to the event.
Time Limit & Cut-off
Marathon - 9 hours (3 hrs, 11:00 a.m. @ 9 mi)
50K - 9 hours (2 hrs 45 min, 10:45 a.m. @ 9 mi; 6 hrs 35 min, 2:35 p.m. @ 21 mi)
All Events - 9 hours
Elevation Profiles/Course Surface
4 mi
Elevation Gain: 400'
Course Surface: Single Track (0%), Dirt Road (100%), Asphalt (0%)
10 mi
Elevation Gain: 2,420'
Course Surface: Single Track (0%), Dirt Road (100%), Asphalt (0%)
Half Marathon
Elevation Gain: 3,420'
Course Surface: Single Track (21%), Dirt Road (76%), Asphalt (3%)
Marathon
Elevation Gain: 6,760'
Course Surface: Single Track (28%), Dirt Road (70%), Asphalt (2%)
50K
Elevation Gain: 8,000'
Course Surface: Single Track (38%), Dirt Road (60%), Asphalt (2%)
Aid Stations
Fully-stocked aid stations every 3 - 5 miles. You can expect fresh fruit, salty snacks, assorted candy, water, and Skratch electrolyte sports drink. It is highly recommended that runners carry at least 20 oz. of water between aid stations.
Cupless
In an effort to reduce waste and litter, Coastal/Zoom events are cupless. We request that you bring your preferred means of containing fluids during your run and at the aid stations. We will have some Hydrapak SpeedCup ($5) for sale at check-in.
Please note that there are no pre-filled cups of hydration at the aid stations. In case you really need a disposable cup, please request one from the aid station volunteers. We ask that you use only one. Thank you!
Results
We use state-of-the-art Bibtags by MyLaps to accurately time each runner’s finish time. Results are published on the website every 30 minutes.
Awards
T-shirts will be given to all pre-registered runners. All finishers will receive a custom medal and 50K finishers will also receive a custom coaster.
Overall Winners: The top 3 male and female overall winners of every distance will win an award and race credits to future Coastal races:
1st Place - $50
2nd Place - $35
3rd Place - $20
These race credits are valid for 3 months from date of issue and is for one time use only.
Top three finishers in each age group and gender will receive award medals.
