Trail Running calendar near Castro Valley 2026-2027

A trail running event in Almaden Quicksilver Park near San Jose with mostly dirt roads and single track on hilly terrain. Multiple distances are offered from 5K up to 50K and course maps are available from the organizer.

Trail races of 10K, half marathon and 30K through Henry Cowell Redwoods State Park with single track, sand ridge and river crossings. Aid stations are spaced every five to six miles and the event is cupless.

Navigate through historic San Francisco neighborhoods and parks in this unique 5K or 10K challenge. Use a custom map to find checkpoints and solve riddles individually or in teams of up to five people.

The Double Dipsea is a longstanding annual 13.7 mile trail race from Stinson Beach to Mill Valley and back, run on mostly single track with many stairs and handicapped starts that create frequent passing among runners.

Obstacle race weekend at Mahon Ranch near Elk Grove on Aug 29-30, 2026 with Sprint, Super and Kids races, team entry options, and service member discounts.

A scenic loop trail race around Angel Island with a single-loop 10K and a half marathon that runs the loop twice; ferry transport is required and included in race pricing, and the field is limited to 400 participants.

Explore the scenic trails of Huddart Park and Bear Gulch at this multi distance trail event. Runners can choose from distances ranging from 8K to 50K through redwood forests and lush ferns.

Explore the gentle trails of Pinto Lake County Park at the Apple City 5k. This inaugural event celebrates the agricultural roots of Watsonville's Pajaro Valley. The race supports local students, with half of its proceeds going to the Pajaro..

Experience the natural scenery of Mount Diablo State Park through a variety of trail races. Runners can select distances ranging from 4 miles to a 50K with spectacular views of the San Francisco Bay Area.

Experience the trails of China Camp State Park with a selection of distances including a 5K 10K and Half Marathon. Participants enjoy a post race festival with beer steins custom medals and local snacks.

Trail races in Tilden Regional Park offering 50K, 35K, half marathon and 10K distances with aid stations every 5 to 7 miles, a cupless format, limited field of 350, technical shirts, and finish awards across multiple categories.

Trail races at Stevens Creek Reservoir include a Half Marathon, 11K and a 2.5 mile charity Lollipop Loop on shaded singletrack and ridge trails. The field is limited and aid stations provide food and drinks.

A trail running event at Calero County Park offering distances from a kids run to a 50K across single-track and dirt roads, with named aid stations, drop bag support, bib color assignments, and time limits for longer races.

Trail running event in Las Trampas Wilderness on September 19, 2026, offering a half marathon, 10K and 5K with hilly trail terrain and scenic vistas. Remote participation options and a parks campership fundraiser are included.

Dick Collins Firetrails in Castro Valley features a 100k, a 50-mile race, and a marathon on Lake Chabot park trails. The event is UTMB Index and the 50-mile race counts toward the Pacific USATF Grand Prix.

Trail marathon, half marathon and 5 mile at Andrew Molera State Park on September 26, 2026. The route follows Old Coast Rd with marked aid stations, a 6.5 hour cutoff and a 300 participant limit.

JP's Backyard Ultra/Hike is a final edition event in Napa's Skyline Wilderness Park. Participants run or hike a 3.3-mile loop, choosing their own distance up to 33 miles. This free event is a fundraiser, with a suggested donation supporting..

Trail races run through shaded redwood forest in Sanborn County Park on Sep 27, 2026, with 50K, half marathon and 10K options and spectator access.

Trailblazer Race in Mountain View offers 10K, 5K, a 3-mile walk and a kids 1-mile run on Stevens Creek Trail and Shoreline Park, plus a festival and activities. Proceeds benefit Friends of Stevens Creek Trail.

Experience a trail half marathon on San Bruno Mountain featuring 2,400 feet of elevation gain and stunning views. Enjoy a scenic route with 93 percent trail coverage followed by a post race meal and finishers medal.