Redtail Ridge
Castro Valley, United States • 21 Feb 2026
Event details
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 distance options:
- 5K (3.1 miles, 110 ft elevation gain)
- 10K (6.4 miles, 650 ft elevation gain)
- Half Marathon (13.1 miles, 1,800 ft elevation gain)
- 30K (18.9 miles, 2,300 ft elevation gain)
- 50K (31.4 miles, 3,800 ft elevation gain)
The event has a total capacity of 500 runners across all distances. The 50K has an 8.5 hour time limit. All races are chip timed using disposable chips attached to the back of each bib. Drop bag services are not available.
Course and logistics
Courses use a mix of moderately technical dirt trails, non-technical fire roads, and some paved sections. Hills can be long; hiking or trekking poles are permitted. Courses are marked with colored surveyor ribbon approximately every 200 meters, with turns marked more heavily; blue ribbons indicate wrong-way trails.
Aid stations provide a variety of food and drinks such as energy gels, chews, Stroopwafels, trail mix, chips, PB&J sandwiches, soda, water, and Skratch Labs hydration. Aid stations carry basic first aid items but not anti-inflammatory medicine. This is a cupless event, so runners must carry their own bottle or reusable cup; collapsible silicone cups will be available for purchase on site. Parking inside the park is free for participants who arrive before lots fill, with additional free roadside parking nearby. Visit the organization's website for the most recent information.