Redtail Ridge

Castro Valley, United States • 21 Feb 2026

Redtail Ridge - Lake Chabot Regional Park

Redtail Ridge is a trail running event at Lake Chabot Regional Park in Castro Valley, CA on February 21, 2026. The event offers multiple distances and uses a course that combines dirt trails, non-technical fire roads, and some paved sections. Much of the course is moderately technical; hills are present and hiking poles are permitted.

Distances include:

  • 5K : 3.1 miles, 110' elevation gain
  • 10K : 6.4 miles, 650' elevation gain
  • Half Marathon : 13.1 miles, 1,800' elevation gain
  • 30K : 18.9 miles, 2,300' elevation gain
  • 50K : 31.4 miles, 3,800' elevation gain

The event is professionally chip timed using MyLaps and Race Director; disposable chips are attached to the back of each bib. Aid stations provide a variety of foods and beverages such as energy gels, chews and stroopwafels, trail mix, PB&J, soda, water, Skratch Labs hydration, and seasonal fruit. This is a cupless event; runners are responsible for carrying their own bottle or reusable cup. Drop bag services are not available.

Parking within the park is included in the entry fee for participants who arrive before lots are full; additional free roadside parking is available. Event capacity is 500 runners across all distances. Awards, finisher medals, and a pint glass for 50K finishers are provided. Visit the organization's website for the most recent information.

Race information

50 km
50k
30 km
30k
Half Marathon
Half Marathon
10 km
10k
5 km
Visit the organization's website for the most recent information.
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