It doesn't get much better than this coastal ridge trail run. Enjoy the rolling single-track high up on Mt. Tam with views of the Pacific Ocean below. You will follow a combination of paved roadways and dirt single-track trails offering striking views of Bolinas Lagoon, the Pacific Ocean and Marin County watershed. From the start at Rock Springs, the course follows Ridgecrest Blvd. along the spine of Bolinas Ridge separating East and West Marin County. 10K runners will take a left at Willow Camp Trail and head back to Rock Springs along the Coastal Trail. The Half Marathon course continues along Ridgecrest Blvd. to Bolinas/Fairfax Road and also returns via the Coastal Trail. The event is limited to 300 participants so don't wait too long to register!
Registration fees
Prices are inclusive of mandatory charges, items, and fees
Half Marathon - Adult
Price changes in 2 months 4 days-
(Age 18 and over)
-
$87.58
Early Bird Pricing
Now registering Jul 10 – Feb 11 -
$98.28Feb 12 – Apr 25
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$108.98Apr 26 – Apr 26
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10K - Adult
Price changes in 2 months 4 days-
(Age 18 and over)
-
$76.88
Early Bird Pricing
Now registering Jul 10 – Feb 11 -
$87.58Feb 12 – Apr 25
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$98.28Apr 26 – Apr 26
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Half Marathon - Youth
Price changes in 4 months 18 days-
(Age 17 and under)
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$34.09
Early Bird Pricing
Now registering Jul 10 – Apr 25 -
$39.44Apr 26 – Apr 26
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10K - Youth
Price changes in 4 months 18 days-
(Age 17 and under)
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$28.74
Early Bird Pricing
Now registering Jul 10 – Apr 25 -
$34.09Apr 26 – Apr 26
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Course Map
COURSE CUT-OFF TIME: 3 HOURS (13:45min/mile pace for half marathoners, 29min/mile for 10Kers). Hikers/Walkers are welcome to participate.
Half Marathon Elevation Profile
Additional Details
ATHLETE CHECK-IN: 7:00 - 7:45 AM. If you receive your bib in the mail, you do not need to check-in. If you need to pick up a bib or change your distance, you can do so at the check in near the Mountain Theater. Safety pins and course maps will also be available during athlete check-in.
COURSE MARKINGS: The course will be marked with orange ribbon. A course monitor will guide the 10Kers on when to turn. The half marathon turnaround is designated by a sign.
AID STATIONS: The 10K has one aid station at mile 5. The half marathon has aid stations at mile 2.35, 7 and 12. There will also be food/drink available at the finish. We highly recommend that you carry water.
INCENTIVES: T-Shirts for all participants. Personalized award ribbons to the top three finishers, male and female, in each age group for all distances which will be mailed out a few weeks after the race.
Medals Awarded to ALL Half Marathon Finishers.
BIB NUMBERS: Bib numbers will be mailed out to participants beginning two weeks before the event. If you do NOT receive a bib prior to race day, you will pick one up on race day morning. If you did not supply a valid mailing address when you registered, or if your mailing address has changed, please e-mail us at info@envirosports.com.
PARKING: is available in the Rock Springs Parking area in Mt. Tamalpais State Park. Parking attendants will guide you on where to go once you enter the park.
DRIVING DIRECTIONS: Google Maps Link to Parking Area.
CANCELLATIONS: Registrations are non-refundable and non-transferable. Here are the policy Terms & Conditions. You cannot purchase it AFTER you have completed your checkout. Otherwise if you didn't email us by March 26, 2025, you may receive a rollover credit (the amount you paid minus a $20 fee) to use toward any future Enviro-Sports race.
HEADPHONES POLICY: Since parts of this race include very narrow trails with steep drop-offs along the course, it is imperative that runners can hear each other in order to pass safely, even if they are running at a slow speed. For safety reasons (and for the enjoyment of your fellow runners) headphones (and any other audio devices) are NOT allowed.
Travel & Accommodations
Many great locations in the Tiburon & Mill Valley area.
Contact information
- Event contact
- Enviro-Sports
- info@envirosports.com
- Phone
- 415-868-1829
- Website
- Visit website