Trail Running calendar near Clayton 2025-2026

The Napa Valley Trail Marathon will take place in Calistoga on Saturday 21 March 2026. You can run between 10 and 26 miles.

The Western Pacific Marathon event, held at Quarry Lakes Regional Recreation Area in Fremont, California, offers runners a choice of half marathon, 10K, and 5K distances. The course is mostly flat, following the historic Western Pacific Trail, which was originally used in the 1800s to transport grav..

The Bad Ass Backyard Ultra (B.A.B.U.) is an 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 or face el..

The Golden Gate Headlands Marathon will take place in Mill Valley on Saturday 4 April 2026. You can run between 10 and 26 miles.

The Diablo Trails Challenge will take place in Walnut Creek on Saturday 4 April 2026. You can run between 5 and 50 kilometers.

The American River Endurance Run, held in Northern California, is the second largest 50-mile race in the United States. Starting in Folsom and finishing in Auburn, it attracts both experienced ultrarunners and newcomers. The event features three races: a 50-mile run from Folsom Point, a 25-mile run..

The Romancing the Island Half Marathon will take place in Belvedere Tiburon on Saturday 11 April 2026. You can run between 10 and 13 miles.

The Lake Sonoma 50 is a premier trail running event held in Healdsburg, California, featuring a 50-mile ultramarathon, a marathon, and the Trail Sisters Half Marathon. Set against the scenic backdrop of Lake Sonoma, the races offer challenging courses through beautiful natural terrain. The event fos..

The Napa Valley Endurance Run is a challenging trail running event held in Calistoga, California, featuring four race distances: 50k, 35k, half-marathon, and 10k. Starting and finishing at the Calistoga Fairgrounds, the courses traverse scenic Robert Louis Stevenson State Park and ascend to the top..

The Badger Cove Half Marathon will take place in Livermore on Saturday 18 April 2026. You can run between 5 and 13 miles.

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 edges of Folsom Lake, the courses feature a mix of runnable single track and double-wide trails with significant ele..

The Mt. Tam Wild Boar Half Marathon will take place in Mill Valley on Saturday 25 April 2026. You can run between 10 and 13 miles.

The Miwok 100K is a renowned trail ultramarathon held near Stinson Beach, California, just under an hour from San Francisco. The challenging 100-kilometer course features 11,800 feet of elevation gain across single-track trails, dirt roads, and a short paved section. Runners enjoy stunning views of..

The Tails & Trails Charitable Walk/Run takes place in Windsor, California, at 11010 Estate Lane. This event offers a 5K run and a Dogwood Dash, with a virtual option allowing participants to complete any distance. The event supports a charitable cause and provides a welcoming atmosphere for runners..

The Muir Woods Marathon, organized by Enviro Sports, is a trail running event held near Stinson Beach, California. It offers multiple race distances including a full marathon, half marathon, and a 7-mile run. The course features scenic trails through the iconic Muir Woods and surrounding natural lan..

The Trailquake will take place in Saratoga on Sunday 10 May 2026. You can run between 5 and 13 miles.

Run for Amma is an annual charity running event held at Skyline Ridge Open Space Preserve in Los Gatos, California, celebrating its 15th anniversary in 2026. The event offers three race distances: a challenging 50K with 5,266 feet of elevation gain, a 30K with 3,629 feet of elevation gain, and a 10K..

The Rim Rock 50 Mile Trail Challenge is an inaugural ultramarathon set for May 16, 2026, in Napa Valley, California. Starting at Skyline Wilderness Park, the race covers approximately 50 miles through rugged, scenic trails including the Napa Open Space Preserve and the newly opened Suscol Headwaters..

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..

The Wildcat Half Marathon will take place in El Sobrante on Saturday 16 May 2026. You can run between 5 and 13 miles.