HALF MARATHON
The Half Marathon course is a hilly, and technical course designed for the experienced trail runner looking for a challenge. Enjoy gorgeous scenery with green meadows, wild flowers, and variety of beautiful trees. The race starts near the Upper Oak Knolls picnic area and climbs into Annadel State Park. The Annadel Half Marathon is a tough course with wet, rocky and rooted terrain. The race will feature chip timing, a free t-shirt, a finisher medal, post-race food and beer!
Parking fee is $8 at the entrance or free with your Sonoma County Regional park pass.
- Date: April 18, 2026
- Time: 9:00 am
- Location: Spring Lake Regional Park, 5585 Newanga Ave., Santa Rosa, CA 95405
- Click here for more information about Annadel State Park.
Parking fee is $8 at the entrance or free with your Sonoma County Regional park pass.