Trail Running calendar near Fairfield 2026-2027

A trail event at Granite Beach on August 23, 2026 offering 5K and 10K courses for runners and their dogs, with finisher medals and dog bandanas; aid stations provide drinks and gels and dogs have their own water.

NorCal Spartan Event Weekend at Mahon Ranch in Elk Grove features Sprint, Super and Kids obstacle races on rolling trails and river crossings, with spectator options and team registration available.

Trail races at Huddart Park, King's Mountain and Bear Gulch offer measured distances from a 50 yard kids dash to a 50K, with fees listed per distance and registration opening November 11, 2025.

A hilly loop race around Angel Island with Half Marathon and 10K options, limited to 400 participants and including the required ferry to the island.

A steep 4.75 mile up and down run, hike, or walk on San Anselmo's Bald Hill that finishes downtown with live music and a t shirt. The third annual event benefits local nonprofits and includes town endorsement.

A PA/USATF cross country race of 3.4 miles at Spring Lake Regional Park in Santa Rosa on August 30, 2026. The 33rd annual Empire Open features rugged dirt trails, three races including a masters division, and a $1,500 prize purse for USATF..

Trail races at Mammoth Bar OHV Area in Auburn State Recreation Area on September 6, 2026. Options include a 13.1 mile half marathon and a 6.2 mile 10K, each with notable elevation gain and staffed aid stations.

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.

A 6.45 miles trail race in Annadel State Park organized by the Empire Runners Club, held in early September with staggered age and gender starts, limited to 100 runners and awards for the top 13 finishers.

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.

A September 12, 2026 trail event in Berkeley featuring 10K, half, 35K and 50K courses through Tilden and Wildcat Canyon with chip timing, regular aid stations and a cupless aid policy.

Trail trail races at Stevens Creek Reservoir in Cupertino on September 12, 2026 include a Half Marathon, 11K and a 2.5 mile Lollipop Loop. The USATF sanctioned event is hand timed, capped for the longer distances, and supports wildfire reli..

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.

Mile Madness is a looped trail endurance event in Auburn, California, held September 18-21, 2026. Timed events run from 3 to 72 hours with a 0.75 mile loop and options including a 100 mile race plus on-site aid and amenities.

Trail runs at Granite Beach on Folsom Lake with new 10 mile and 5K courses, aid stations, age group awards, a finisher beer glass and a postrace meal.

Rocky Ridge is a trail running event at Las Trampas Wilderness in San Ramon, California on September 19, 2026. It features a half marathon plus 10K and 5K courses with uphill trail sections and scenic vistas.

The Healdsburg Fitch Mountain Footrace is a long running community event in Sonoma Wine Country that raises funds for Corazón Healdsburg and a kids running team. It features 3K and 10K courses beginning and ending near the Historic Downtown..

A set of trail races at Lake Chabot in Castro Valley offering a Bay Ridge 100k, Firetrails 50 and Golden Hills Marathon with published course and aid station plans, set time limits, UTMB indexing, and finisher awards.

A community ultramarathon and hike at Skyline Wilderness Park in Napa, CA, featuring a 3.3-mile loop repeated up to ten times in an hourly format to raise funds for the Pheo Para Alliance.

Trail running in shaded redwood forest at Sanborn County Park on September 27 2026, with 10K, half marathon and 50K options; steep singletrack, shuttle parking, chip timing and specific mandatory gear for the 50K.