⚠️ 2027 edition: provisional information
The date is estimated from the 2026 edition (April 18, 2026), on the same day of the week. Courses, start times, fees and description are carried over from the previous edition: check them on the official website. This page will be updated as soon as the organizer publishes them.
Available distances
About
The Annadel Half Marathon takes place in Santa Rosa, California, in mid-April, and is a hilly, technical, demanding course best suited to experienced trail runners. The half marathon (13.1 miles) starts at 8:00 AM, with the 10K (6.2 miles) and 5K (3.1 miles) following at 8:15 AM. Runners start at the Spring Lake Oak Knolls picnic area and head toward Annadel State Park, passing meadows and a variety of tree species. The 5K is an out-and-back route along a gravel fire road. As a nonprofit event, it aims to raise funds to make the park more appealing to the community.
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Races nearby
Other upcoming races around Santa Rosa.
IPA10K Brewfest & Beer Mile
Oct 31, 2026 · Sebastopol, CA · 6 mi away
13.1 mi · 6.2 mi · 1.9 mi
Napa Valley Marathon
Feb 28, 2027 · Calistoga, CA · 12 mi away
26.2 mi · 13.1 mi · 3.1 mi
Napa Valley Endurance Run
Apr 11, 2027 · Calistoga, CA · 12 mi away
31.1 mi · 21 mi · 13.4 mi · 6.2 mi
Napa Valley Trail Marathon, Half Marathon & 10K
Mar 20, 2027 · Calistoga, CA · 13 mi away
26.2 mi · 13.1 mi · 6.2 mi
Lake Sonoma 50 Mile
Apr 10, 2027 · Healdsburg, CA · 14 mi away
50.3 mi · 26.1 mi · 13 mi
Lake Sonoma 100K, 50K & Trail Sisters Half
Apr 10, 2027 · Geyserville, CA · 25 mi away
62.1 mi · 31.1 mi · 13.1 mi