Boulder Rez Marathon

The Holy COW Trail Stampede is a trail running event held in Westminster, Colorado, featuring distances including a 5K and a 10-mile race. Participants enjoy a fun, community-focused atmosphere with a western theme, running through scenic trails near the Westminster Promenade Terrace. All runners re..

Dirt Circus - Boulder is a free community running event held in Boulder, Colorado, celebrating local trail running culture. Organized by UltraSignup, the event features a social group run with options of a casual 4.5-mile or 10K route through the local trails. Beyond running, the festival offers foo..

The Byers Peak Stampede Half Marathon & 5K Run takes place in Fraser, Colorado, nestled in the Rocky Mountains about 60 miles from Denver. The event features a challenging half marathon and a 5K race, both held on dirt roads and trails with stunning mountain views. The half marathon course starts at..

The Westminster Night Trail is an annual night running event held at Standley Lake in Westminster, Colorado. Celebrating its 12th year, it offers a festive atmosphere with music and lights, showcasing Colorado’s natural beauty under the stars. The course features 100% packed dirt trails, including s..

Front Range Ultra Dayze is an ultra-running festival held in Loveland, Colorado, featuring a variety of ultra-distance events including 50k, 100-mile, 200-mile, and timed races from 12 to 100 hours. The course is a flat, fast 2-mile loop with 80% dirt trail and 20% pavement, set in Centennial Park a..

The Calarat Challenge Trail Running Festival takes place in Jamestown, Colorado, at the scenic Cal-Wood Education Center and Balarat Outdoor Education Center. Held over Labor Day weekend, the event features multiple trail races including a half marathon, 10K, 5K, Kids 1K, and combination races like..