Redtail Ridge

Castro Valley, United States • 21 Feb 2026

Event overview

The Chabot / Redtail Ridge Trail Run takes place on February 21, 2026, at Lake Chabot Regional Park in Castro Valley, California. The event offers multiple distances and has a total capacity of 500 runners. The 50K race has an 8.5 hour time limit. Parking at the park is included in the entry fee for participants who arrive before lots fill; additional free parking is available along the road outside the park. Races are chip timed using disposable chips attached to the back of each bib.

Course and logistics

Distances:

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

Most of the routes use moderately technical dirt trails and non-technical fire roads, with some paved sections. Hiking or trekking poles are permitted. Courses are marked with colored ribbon, laminated signs, and flour arrows where allowed; blue ribbons mark wrong-way trails. Aid stations supply a variety of food and hydration options (examples include energy gels, Stroopwafels, trail mix, PB&J, soda, water, and Skratch Labs hydration). This is a cupless event; runners must carry their own bottle or reusable cup. Reusable cups will be available for purchase on-site. Awards include custom trophies for the top three overall finishers, finishers’ medals for all, a pint glass for 50K finishers, and age-group medals across listed categories. Volunteers receive a shirt, food, and event credit for service. Visit the organization's website for the most recent information.

Race information

50 km
50k
30 km
30k
Half Marathon
1/2 Marathon
10 km
10k
5 km
Visit the organization's website for the most recent information.
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