Redtail Ridge

Castro Valley, United States • 21 Feb 2026

Redtail Ridge at Lake Chabot Regional Park in Castro Valley, CA offers multiple distances: 5K, 10K, Half Marathon, 30K, and 50K. The course unfolds on a mix of moderately technical dirt trails and non-technical fire roads, with some paved sections, and features rolling hills that reward pacing and technique. Elevation gains range from about 110 ft for the 5K up to 3,800 ft for the 50K. The event emphasizes a cupless format with supportive aid stations, a well-staffed finish area, and race-day shirts. Capacity is 500 runners; dogs on leash are allowed; volunteers and spectators welcome in this scenic Bay Area trail run. Visit the organization's website for the most recent information.

Race information

50 km
3800 m+
50k
30 km
2300 m+
30k
21 km
1800 m+
Half Marathon
10 km
650 m+
10k
5 km
110 m+
Visit the organization's website for the most recent information.
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