Redtail Ridge Trail Run
Castro Valley, CA
- 50K, 30K, Half Marathon, 10K, 5K
- Road (Paved), Trail (Unpaved)
- Official race website
Lake Chabot Regional Park was established in the 1960s after the reservoir had been closed to recreational use for 91 years. Today, the lake remains as an emergency water supply and is open to fishers and boaters, as it is filled with trout, catfish, bass, crappie, and other fish. With … MORE
Local Historical Weather (Feb 21):
| 2026 | 2025 | 2024 | 2023 | 2022 | |
| H (°F) | 61 | 67 | 61 | 58 | 57 |
| L (°F) | 39 | 46 | 48 | 45 | 41 |
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Familiar Course, "New" Organizer, Great!
Inside Trail's Redtail Ridge is run along the shore and in the hills around Lake Chabot. The 5K course is along the lake's eastern shore, out and back. Just after … MORE
Inside Trail’s Redtail Ridge is run along the shore and in the hills around Lake Chabot. The 5K course is along the lake’s eastern shore, out and back. Just after the 5K turn-around, the 10K, half marathon, 30K, and 50K courses head for the hills. Being February, it was chilly, probably under 45F at the starts, there was some mist on the lake, and the trees and hills were very green. All in all, beautiful courses.
Inside Trail has been operating, generally, and doing this event for many years. So everything is well organized and runs smoothly. The T-shirt and finisher’s medal feature a redtailed hawk. Age group winners are 3-deep and by decade, and winners were given a choice between a slate-like coaster or a magnet with the name and race info (I got age group first, Geezer Privilege!). In 2016, age group awards were a simple medal with Inside Trail’s logo and the ordinal place number.
There was not an aid station on the 5K course (1.55 miles out and back not surprising). There were plenty of water, electrolyte drink and snacks in the finish recovery area (a picnic area with quite a few tables.
I will definitely consider doing Redtail Ridge in 2027!
Go go go, Chabot!!
What an awesome race!! Beautiful course at Lake Chabot. You do the 30k from Marina to Brandon, to Woolridge, back to Brandon, back to the Marina, then you go out … MORE
What an awesome race!! Beautiful course at Lake Chabot. You do the 30k from Marina to Brandon, to Woolridge, back to Brandon, back to the Marina, then you go out and do the half, Marina to Brandon, then back to Marina. I ended with 31.4 miles and 4.700′ of gain. Amazing crew and volunteers. Lots of fully stocked aid stations, with super nice volunteers. AS are at miles: 4.8, 10.6, 14.1, 18.6, 23.1, and 26.4. Finishers get a great shirt, an awesome medal, and like always a super cool pint glass (with a sticker!) Thanks ITR! Awesome race!
Tough muddy race
This race took place at Lake Chabot Regional Park in Castro Valley. Because of all the rain and flooding, we had an altered course that added a little extra mileage … MORE
This race took place at Lake Chabot Regional Park in Castro Valley. Because of all the rain and flooding, we had an altered course that added a little extra mileage and elevation to the 30k. The distance was 18.7 miles and 2950ft of elevation.. This is my first time running the Redtail Ridge 30k, although I have run at Lake Chabot previously and also I have run with Inside Trail before at their Peacock Gap race in San Rafael. The only thing I can say about this race is that the mud was insane. There were several sections that it felt like we were skiing without poles. There was so much slipping, sliding, and falling happening. I fell twice. I skinned up both knees, but it wasn’t too major. Some sections of the course were perfect to run on, but most had streams of water either flowing down, across the trail or puddled. The trails at Lake Chabot run through eucalyptus forests, grassy meadows, lakeside paths, and hill top vistas. It really is a beautiful place to visit.
There were three aid stations on course that were heavily stocked with Gu Energy gels and chews, Larabar, trail mix, pretzels, potato chips, Oreo cookies, Pop Tarts, boiled potatoes with salt, Coke, Mountain Dew, Ginger Ale, water, Tailwind Endurance Fuel, PB&J sandwiches, M&M’s, Mike & Ike’s, salt tablets, and tangerines. It was easy to stick around and eat, but the run must go on.
At the finish we received out medal and tech tee race shirt. Post race food consisted of hot soup, sausages and buns, pastries, sweet and salty snacks, beer, chocolate milk, water and soda. The soup was really nice because I got chilled off from running in the puddles and mud. It warmed me up until I was able to change my socks and shoes.
Inside Trail is a wonderful racing company. I will definitely sign up for another one of their races, mostly likely Reservoir Dogs 35k on July 1st.
Well organized and scenic!
Super fun, scenic run! I love trail races and Inside Trail always puts on a good race. I was under prepared for this one - this run is supposed to … MORE
Super fun, scenic run! I love trail races and Inside Trail always puts on a good race. I was under prepared for this one – this run is supposed to be significantly easier than the Tilden trail but it felt harder. Lots of hills but the end is all downhill… that always helps 🙂
Great organization and very scenic!
Inside Trail puts on great races, and this one was no different. The trails were extremely well-marked and the aid stations well-stocked. As for the course, there were at least … MORE
Inside Trail puts on great races, and this one was no different. The trails were extremely well-marked and the aid stations well-stocked. As for the course, there were at least 3 very tough climbs with other small rollers interspersed. The terrain was mostly wide, well-maintained trails with a short gravel portion after the first aid station and paved trail to bookend the race. Lots of snacks and drinks at the end, which I appreciated!
I rated the swag at a “3” because I opted not to get a t-shirt to save $5, but other Inside Trail t-shirts were nice and gender-specific, though a bit on the snug size (i.e. order one size up!). The medals are fine, but I’m no medal freak, so I could care less. In fact, they used to give out glassware instead of medals, and I wish they still gave out ceramic mugs!
FYI, this race sold out (all distances) so register early!