Trail Running calendar near Fairfield 2025-2026

Tackle iconic Marin Headlands and Mt Tamalpais on rugged coastal trails in the Marin Ultra Challenge, with 50 Mile and 50K options. Limited to 450 runners, the race offers live tracking, full aid stations, and finisher medals.

Event overview Rattlesnake Dick takes place on March 21, 2026, in Cool, California, with the race base at the Cool Staging Area (7200 Saint Florian Court, Cool, CA 95614). Distances offered: 50K 25K 10K The 50K has 4,700 ft elevation gain..

Event overview The Napa Valley Trail event takes place on Saturday, March 21, 2026, at Bothe-Napa Valley State Park in Saint Helena, California. The race is limited to 300 participants. Distances offered: Marathon Half Marathon 10K The ev..

Redwood (Spring) Trail Run is held at the Chabot Space & Science Center in Oakland, California, featuring multiple distances from 5 miles up to 50K, plus a Half Marathon, Marathon, 30K, a 5K, and several youth events. The course winds throu..

Run the scenic Lag Bon 10K on Sunday, March 22, 2026, along lakeside trails in Fairfax for a springtime challenge. Proceeds support Evidence Action's Safe Water Now program in honor of World Water Day.

Take to the historic Western States trail in Auburn on March 28, 2026 with 5K, 10K, half marathon or a rugged 35K featuring No Hands Bridge and big climbs. Mostly technical dirt, this cupless race asks you to bring your own bottle.

Enjoy a scenic trail run along the historic Western Pacific route at Quarry Lakes in Fremont on March 28, 2026, with half marathon, 10K, 5K or remote entries. Brazen Racing welcomes runners, walkers and hikers on a mostly flat dirt and grav..

Join the Bad Ass Backyard Ultra in Rio Linda on March 28 2026, a repeated 4.16 mile loop starting each hour. Keep running until you are the last person to complete a loop and claim victory.

Event details The 41st annual Golden Gate Headlands race takes place on Saturday, April 4, 2026, at the Marin Headlands Visitor Center and Fort Barry area in Mill Valley, California. The event offers multiple distances: Marathon Half Marat..

Event overview The American River Endurance Runs are a set of trail races that finish in Auburn and use the City of Folsom as the start and hospitality host. The event includes a 50-mile ultramarathon that follows the American River Parkway..

Experience scenic trail running on Mount Diablo with distances from 5K to 50K at the Diablo Trails Challenge on April 4, 2026. Enjoy community vibes and a post race BBQ while supporting Save Mount Diablo.

Event overview The 35th annual Romancing the Island event takes place on April 11, 2026 at Angel Island State Park, Belvedere Tiburon, CA. The race offers two distances: Half Marathon - completes the island loop twice 10K - single loop aro..

Join TERREX Lake Sonoma for a weekend of scenic trails with a Western States qualifier 100K, a 50K and the Trail Sisters women only half. Enjoy lake views, big climbs, camping and cupless aid stations with shuttles to Lone Rock.

Explore Napa's wild side on scenic single track and fire roads around Mount St Helena, starting and finishing at the Calistoga Fairgrounds Great Lawn. Choose from 10K to 50K distances, with UTMB Index status for select races.

Run the scenic Horseshoe Lake Trail Run at Skyline Ridge in La Honda on April 18, 2026, with distances from 5 mile to 50K and a free kids dash. Expect rolling ridge single track, aid stations, and a friendly festival atmosphere.

Event overview Badger Cove Half Marathon/10K/5K 2026 takes place on April 18, 2026, at Del Valle Regional Park in Livermore, California. The event includes on-site race options at Lake Del Valle and a remote runner option. Hikers and walker..

Take on scenic lakeside single track and double wide trails around Folsom Lake with 25K, 50K and 50M options at Outlands Endurance Race. Enjoy stocked aid stations, a post race meal and custom finisher awards.

The Canyons Endurance Runs will take place in Auburn from Friday 24 April 2026 to Saturday 25 April 2026. You can run between 25 and 161 kilometers.

Event The 2026 Mt. Tam Wild Boar Half Marathon & 10K takes place on April 25, 2026, at Mt. Tamalpais State Park in Mill Valley, California. The event is limited to 300 participants. Distances offered: Half Marathon 10K Course and logi..

Run the Miwok 100K from Stinson Beach through scenic Marin single track trails and big climbs. Run solo or as a four person relay; this UTMB index race and Western States qualifier champions sustainability.