Redtail Ridge
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Event overview
The Redtail Ridge (Chabot) Trail Run takes place at Lake Chabot Regional Park in Castro Valley, CA on February 21, 2026. The event offers multiple distances with a total field capacity of 500 runners. There is an 8.5 hour time limit for the 50K and 30K races; all runners must be off course by 5:00 PM. Parking at Lake Chabot Regional Park is free for participants who arrive before lots are full; additional free parking is available along the road outside the park.
- 50K - 31.4 miles, 3,800 ft elevation gain
- 30K - 18.9 miles, 2,300 ft elevation gain
- Half Marathon - 13.1 miles, 1,800 ft elevation gain
- 10K - 6.4 miles, 650 ft elevation gain
- 5K - 3.1 miles, 110 ft elevation gain
Course, support, and logistics
Courses run mainly on moderately technical dirt trails and non-technical fire roads, with some paved sections. Courses are marked with colored ribbons placed about every 200 meters; blue ribbons indicate wrong-way trails. Hiking poles are permitted. Races use disposable chip timing attached to the back of each bib.
Aid stations supply a variety of gels, snacks, drinks, Skratch Labs hydration mix, and basic first aid items (no anti-inflammatory medicine). Runners are strongly encouraged to carry at least one 20 oz bottle. This is a cupless event; runners must carry their own water bottle or reusable cup (reusable cups available for purchase at the event). Drop bag services are not available. Shirts are guaranteed for those who register by February 7, 2026. Awards include custom trophies, medals, and age-group prizes. Visit the organization's website for the most recent information.