Redtail Ridge
Castro Valley, United States • 21 Feb 2026
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 trail distances with a total field capacity of 500 runners. Races are professionally chip timed using MyLaps and Race Director; disposable timing chips are attached to the back of each bib. There is an 8.5 hour time limit for the 50K race.
- 50K - 31.4 miles, 3,800 ft elevation gain
- 30K - 18.9 miles, 2,300 ft elevation gain
- Half - 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 and logistics
Courses run mainly on 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 at critical sections; blue ribbons indicate wrong-way trails. Aid stations provide a variety of fuel and electrolytes (examples include gels, Stroopwafels, trail mix, salty snacks, water, Skratch Labs mixes and cola) and carry basic first aid items. This is a cupless event: runners must carry their own bottle or reusable cup; collapsible cups are available for purchase at events. Parking at Lake Chabot is included in the entry fee for participants who arrive before lots are full; additional free parking is available along the road outside the park. Dogs are allowed on leash in the parks; runners who choose to run with a dog must start at the back of the pack. Visit the organization's website for the most recent information.