Fourmidable

The Trail Run at Sly Park - Summer is a scenic trail running event held at the Sly Park Recreation Area in Pollock Pines, California, within the El Dorado National Forest. The race offers multiple distances including 5K, 10K, 8 Mile, Half Marathon, 17 Mile, Trail Marathon, and a 50K ultra. Courses w..

The Mammoth Bar Trail Runs, hosted by Skybreaker Racing, is a new trail running event held in Auburn, California, within the Auburn State Recreation Area. Scheduled for September 7, 2025, the event offers three race distances: a half marathon, 10K, and 5K. The courses traverse the single-track and d..

The Gold Rush Growler Trail Runs, held at Granite Beach in Folsom Lake State Recreation Area, feature scenic 10-mile and 5K trail races along shoreline and single-track trails. The 10-mile course includes diverse terrain with paved park roads, secret trails, and notable landmarks like Oak Point, Dot..

The Sunset & Cider Trail Races, held in Auburn, California's scenic American River Canyon, offer three trail running distances: 50K, 13 miles, and 5 miles. The courses feature mostly runnable single-track trails with some short neighborhood road sections and varying elevation gains—3,875 ft for the..

The Auburn Half Marathon, held in Auburn, California—known as the Endurance Capital of the World™—offers trail running on the scenic Western States Trail. The event features a half marathon, 12K, and 5K races, all starting from Auburn Overlook Park and winding through the Auburn State Recreation Are..

The Yuba Gold Trail Runs take place near Nevada City, California, in the scenic gold country region. The event offers multiple distances including a 50K, 35K, and half marathon, all featuring beautiful views of the South Fork Yuba River and the historic Malakoff Diggins hydraulic mining site. The st..