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Annadel Half Marathon

Santa Rosa, United States • 18 Apr 2026

Event overview

The Annadel Half Marathon is a non-profit fundraising race held on April 18, 2026, at Spring Lake Regional Park, 5585 Newanga Avenue, Santa Rosa, CA. The event has operated for about 15 years and donates a portion of proceeds to Trione-Annadel State Park and the Sonoma County Parks Foundation. Organizers describe the course using the trails of Annadel State Park and emphasize park stewardship and low-waste practices in honor of Earth Day (April 22).

Race details

Distances offered:

  • Half Marathon
  • 10K
  • 5K

The Half Marathon has a 4-hour cut-off time. Each participant receives a race medal, an event shirt, and post-race beverages and snacks. The event uses cup-free aid stations and refill options to reduce waste. Registration is non-refundable. 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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