Sean O'Brien 100K

The Malibu Canyon Trail Races, presented by Keira Henninger, take place in Malibu, California, within the scenic coastal Santa Monica Mountains. This challenging event offers multiple distances including 100K, 50-mile, 50K, 30K, and a half marathon, all run on single track and fire roads through rid..

The Griffith Park Trail Marathon Relay & 8K is a celebrated running event held at Park Center in Griffith Park, Los Angeles. Recognized by Runner’s World as one of the "10 Best Races You’ve Never Heard Of," it offers both a marathon relay for teams of up to five and an 8K race for solo runners. Part..

The Red Rock Rumble is a challenging 10k trail race held in the stunning Red Rock Canyon of Topanga, California. Featuring steep climbs, rugged terrain, and breathtaking views of the Santa Monica Mountains and Pacific Ocean, the course includes 1,360 feet of vertical gain and loss, with a mix of fir..

Tough Mugu is a challenging trail running event held at La Jolla Group Campground in Point Mugu State Park, Malibu, California. It features two main distances: a 25k and a 10k course, both offering stunning coastal mountain views. The 25k course covers 15.75 miles with 2,427 feet of elevation gain,..

The SoCal Summer 6K/12K, organized by Pasadena Running Company, is a vibrant trail running event set in Lower Arroyo Park, Pasadena. Participants can choose between two distances: a 6K and a 12K trail run, both designed to showcase the area's beautiful interconnected trails. The event features a wav..

The Bulldog Ultra, held in Malibu Creek State Park, Calabasas, CA, is Southern California's oldest 50k trail race, celebrating over 30 years. Scheduled for August 16, 2025, it offers two distances: a challenging 50k ultra with 29.4 miles and 5,784 feet of elevation gain, and a 25k trail run covering..