Annadel Half Marathon

APR

18

2026

Run the scenic trails of Annadel State Park at the Annadel Half Marathon in Santa Rosa on April 18, 2026, with half marathon, 10K, and 5K options for all paces. Proceeds support Trione Annadel State Park and Sonoma County Parks Foundation.

Sat 18 Apr 2026

Santa Rosa, California

Registration

Half Marathon 10 kilometers 5 kilometers

Always double-check with the organizer's website! This page may contain affiliate links.

Event overview

The Annadel Half Marathon is a nonprofit fundraising running event held on April 18, 2026, at Spring Lake Regional Park, 5585 Newanga Avenue, Santa Rosa, CA. The event includes races that use the scenic trails of Annadel State Park. A portion of event proceeds is donated to Trione-Annadel State Park and the Sonoma County Parks Foundation. The event has a no-refund policy.

Race details

Half Marathon - 4-hour cut-off
10K
5K

Each participant receives a race medal, an event shirt, and post-race beverages and snacks.

Sustainability and fees

The event is organized as a low-waste event with cup-free aid stations, refill options, and a focus on park stewardship. Registration fees vary by distance and date. Published price ranges are: Half Marathon from $108.98 to $130.38; 10K from $60.83 to $76.88; 5K from $55.49 to $66.18. Visit the organization's website for the most recent information.

Half Marathon

10 km

10k

5 km