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Annadel Half Marathon

Santa Rosa, United States • 18 Apr 2026

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.

United States California Santa Rosa

Race information

Registration
Half Marathon
Half Marathon
10 km
10k
5 km
Visit the organization's website for the most recent information.
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