Trail Running calendar near Clayton 2025-2026

The Coyote Hills Run takes place at Coyote Hills Regional Park, located at 9400 Quarry Road in Fremont, California, along the eastern shoreline of San Francisco Bay. This event offers multiple race distances including a 5K, 10K, and a half marathon, welcoming both runners and hikers. The park is not..

The Mt. Umunhum Trail Conquest - Winter is a trail running event held at Almaden Quicksilver County Park in San Jose, California. The race offers multiple distances including a 50K, marathon, 30K, half marathon, 7-mile, 5K, mile, and a kids run.The longer courses traverse the scenic Sierra Azul Open..

Bay Breeze in San Leandro, California, is a scenic running event featuring a half marathon, 10K, and 5K distances. Held at the San Leandro Marina Park, the course offers mostly flat, easy bayside trails that stay close to the water, providing romantic vistas of San Francisco and the Bay. The event w..

The Bad Ass Backyard Ultra (B.A.B.U.) is a challenging endurance running event held at Dry Creek Parkway in Rio Linda, California, near Sacramento. Participants run a 4.16-mile loop every hour, starting on the hour, with each loop called a "yard." Runners must be ready to start each new loop on time..

The Napa Valley Endurance Run is a challenging trail running event held in Calistoga, California, starting and finishing at the Calistoga Fairgrounds. It offers four race distances: 50k, 35k, half-marathon, and 10k, all traversing scenic and rugged terrain through Robert Louis Stevenson State Park a..

The Outlands Endurance Race, held at Peninsula Campground in Pilot Hill, California, offers challenging trail running distances of 25K, 50K, and 50 miles. Set along the rugged, scenic trails bordering Folsom Lake, the course features a mix of singletrack and double-wide trails with significant eleva..

Run for Amma is an annual charity running event held at Skyline Ridge Open Space Preserve in Los Gatos, California, supporting UCSF cancer research. Celebrating its 15th anniversary, the event offers three race distances: a challenging 50K with 5,266 feet of elevation gain, a 30K with 3,629 feet of..

The Rim Rock 50 Mile Trail Challenge is an inaugural ultramarathon held in Napa Valley, California, centered at Skyline Wilderness Park. The race features a challenging 50-mile solo course or a 50-mile relay for teams of two, traversing rugged trails through Skyline Wilderness Park, Napa Open Space..

The Napa Wilderness Trail Runs, held at Skyline Wilderness Park in Napa, California, offer a variety of trail running distances including 10K, 21K (half marathon), 30K, and a challenging 50K ultra marathon. The courses feature scenic routes with steep climbs, notably the Rim Rock Trail, providing st..