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Annadel Half Marathon

Santa Rosa, United States • 18 Apr 2026

Annadel Half Marathon

The Annadel Half Marathon event takes place on April 18, 2026 at Spring Lake Regional Park, 5585 Newanga Avenue, Santa Rosa, CA. The event includes a half marathon plus shorter distances on the park trails and supports local park stewardship.

Distances:

  • Half Marathon (4 hour cut-off)
  • 10K
  • 5K

This is a non-profit fundraising event that has supported Trione-Annadel State Park for more than 15 years. A portion of event proceeds is donated to Trione-Annadel State Park and the Sonoma County Parks Foundation. The organisers operate the event as a low-waste effort in honor of Earth Day, with cup-free aid stations, refill options, and an emphasis on leaving the park in better condition.

Each participant receives a race medal, an event shirt, and post-race beverages and snacks. The event is presented as a community running day on the scenic trails of Annadel State Park. Registration is required and fees apply. The event policy states that there are no refunds. 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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