Trail Running calendar near Fairfield 2025-2026

Gold Rush Growler Trail Runs at Granite Beach, Folsom Lake SRA, offer a 10-mile trail run and a 5K along the shoreline and trails. For 2025, the courses are new: the 5K starts at Granite Beach, to Oak Point and Old County, then returns on new and old trails; the 10-mile route starts at South Granite..

The Mt. Umunhum Marathon, Race to the Top and Down, is a challenging trail running event held in Almaden Quicksilver County Park, San Jose, California. This marathon features a rugged course that begins at the Hacienda Entrance and ascends to the summit of Mt.Umunhum, one of the prominent peaks in t..

Rocky Ridge is a trail race set in the Las Trampas Wilderness near San Ramon, California. The event offers a half marathon, a 10K, and a 5K through rugged hills and scenic vistas. The course is demanding and not beginner-friendly, rewarding perseverance with trails and views few runners will see, fo..

Rebels XC Challenge is a cross-country running meet held in Carmichael, California, at 6700 Tarshes Drive. The event is scheduled for September 20, 2025, and offers three divisions: Women’s Race, Masters Men, and Open Men. Distances are not listed on the page, and course specifics aren’t described,..

The Dick Collins Firetrails will take place in Castro Valley from Saturday 27 September 2025 to Sunday 28 September 2025. You can run between 42 and 100 kilometers.

Pacifica Summit Run, staged at San Pedro Valley State Park in Pacifica, California, features 10K and half-marathon trail races hosted by Urban Coyote Racing. Runners enjoy postcard views of the Pacific Ocean coastline and plenty of switchbacks as they ascend the summit on the upper San Francisco Pen..

JP's Backyard Ultra/Hike is a grassroots ultramarathon and hike held at Skyline Wilderness Park in Napa, California. In its third year, the event features a 3.3-mile loop with 550+ feet of climbing through rocky and shaded trails. Runners and hikers may do 1 to 10 loops, starting together on the hou..

The Sunset & Cider Trail Races take place on September 27, 2025, in Auburn, California. The start and finish are at Ponderosa Cider Co, 102 Gum Lane, near Auburn Overlook Park. The event is presented by BAD LUCK RUN CLUB and is set on trails along the American River Canyon. 50K - two out-and-..

Spartan Trail San Jose Challenge takes place at Sanborn County Park in the eastern Santa Cruz Mountains near Saratoga, California, with the race site at West Valley College Parking Lot 5. The event offers three trail distances: 50K, 21K, and 10K. Runners tackle well‑groomed yet steep and difficult t..

The Trailblazer Race in Mountain View, CA, is an annual family-friendly event featuring 10K and 5K runs, plus a 3-mile walk along the scenic Stevens Creek Trail and Shoreline Park. The courses are fast, flat, and stroller-friendly, offering beautiful views of wildlife, salt ponds, and surrounding mo..

Set in Auburn, California, just off Highway 80 in Gold Country, the Auburn Half Marathon is a trail-running event offering three distances: a half marathon, 12K, and 5K. Runners depart from Overlook Park, head toward Robie Point, cross No Hands Bridge, climb toward Cool, and loop back to finish at O..

The Women's Headlands Half Marathon is a scenic 13.2-mile trail race held annually in the Marin Headlands near Mill Valley, California. Celebrating its third year in 2025, the event features a challenging course with nearly 2,000 feet of elevation gain, showcasing stunning singletrack trails, sweepi..

Star City San Bruno Mountain Half Marathon & 5K, organized by the Excelsior Running Club, takes place in Brisbane, CA, on the San Bruno Mountain trails. The course is 93% on trail with about 2,400 feet of elevation gain, including a single-track downhill and sweeping views of the Pacific, Bay, and S..

The Women's Headlands Half Marathon is a trail running event held in the scenic Marin Headlands near Mill Valley, California. This race features a brand-new half marathon course that highlights the area's stunning singletrack trails, challenging climbs, and exhilarating descents, offering runners a..

The Reservoir Dogs Trail Run takes place at the San Pablo Reservoir / Briones Reservoir area (East Bay Municipal Utility District), Orinda / El Sobrante, CA, on October 4, 2025. Distances offered are: 35K : 23.4 miles, 2,800 ft elevation gain Half Marathon : 13.9 miles, 1,450 ft elevation gain 10K..

Mile Madness Endurance Run takes place at Sunset Whitney Recreation Area in Rocklin, California. The race uses a 1.05-mile loop (85% dirt, 15% paved) with about 62 feet of elevation per lap and a central Start/Finish hub. Runners choose from 6-, 12-, 24-, 48-, or 72-hour events, plus a 100-mile chal..

Granite Head 2025, billed as Granite Bay’s Best Trail Run and part of Trails & Ales, is a two-distance trail race presented by Altra in Granite Bay, California. Runners can tackle a gnarly 6.6-mile short course or an epic 11.2-mile long course. Both start and finish at Granite Beach, with the course..

The Mt. Umunhum Trail Conquest-Fall is a trail running event held at Almaden Quicksilver County Park in San Jose, California. The race offers multiple distances including a 5K, 7 Mile, Half Marathon, 30K, Trail Marathon, and 50K.The longer courses venture into the scenic Sierra Azul Open Space Prese..

Go Wild Marin offers a trail and wilderness navigation challenge in Corte Madera, California, with 2-hour and 4-hour options. Teams of 1 to 5 use a custom map to locate up to 24 checkpoints scattered along trails and wild areas of the Tiburon Peninsula. The event emphasizes exploration and navigatio..

Ruth Anderson Memorial Endurance Run is an ultramarathon held in San Francisco, California, circling Lake Merced. Runners complete a multi-lap course on a 4.475-mile paved bike path, with aid stations at the start/finish and each loop. The event features distances associated with a 50M designation,..