O'Neill Park Trail Races

The Rock It in Chino Hills 5K & 10K is a trail running and hiking event held at Chino Hills State Park in Brea, California. Participants can choose between a 5K or 10K course that showcases the park's stunning and expansive trails, offering scenic views and a tranquil outdoor experience. The race in..

Live Oak Odyssey is a fixed-time trail running event at O'Neill Regional Park in Trabuco Canyon, CA (30892 Trabuco Canyon Road). The event offers two timed options: 6-hour fixed-time event 3-hour fixed-time event Each lap is approximately 2.75 miles with about 500 feet of vertical gain per loop...

Casper's Trail Races on Oct 25, 2025, take place in San Juan Capistrano, California, offering trail distances: 10K, 13.2 miles, 30K, marathon, and 50K. The event, hosted by KHraces, aims for a well-supported, well-marked experience with swag, highlighting Orange County’s fall trail atmosphere. While..

The event takes place at Bill Barber Memorial Park in Irvine on Sunday, October 26, 2025. Distances offered: 5k 10k 15k Half marathon The course is an open route on a shared path and uses out-and-back loops that will be marked. Specific loop formats listed are: 5k as an out-and-back route, 10k a..

The Machete Muertos 200 is an ultramarathon event held at Lake Perris, California, featuring multiple race distances including 10, 20, 50, 100, and 200 miles, plus a 20-mile ruck division. The course consists of challenging loops with significant elevation gains—2,300 feet per lap for shorter distan..

The Chino Hills Trail Run Series, held at Chino Hills State Park in Brea, California, offers challenging trail races in scenic natural surroundings. The fall event features 30K and 50K distances, with well-marked courses that traverse hilly terrain and showcase native plants and wildlife. Aid statio..