Trail Running calendar near Nederland 2025-2026

The Lory Summer Trail Series, taking place from August 5 to August 26, 2025, offers a series of midweek trail races designed for both novice and experienced runners. Participants can choose from distances ranging from 5K to 12K, with courses that vary in elevation and difficulty. The event aims to c..

The Eltuck Valley 5K is part of a series of midweek trail races held at Lory State Park in Bellvue, Colorado. Scheduled for August 5, 2025, this event is designed to cater to both novice and experienced runners, offering a flat and fast course ideal for those looking to improve their speed. Particip..

The Run the Rockies Trail Race is a scenic event featuring a 5k, 10k, and half marathon through the trails of Frisco Peninsula, offering stunning views of Dillon Reservoir and the Ten Mile Range. The courses include single track and dirt roads, starting and finishing at the Frisco Nordic Center. Par..

The Holy COW Trail Stampede is an exciting running event held in Westminster, Colorado, featuring a 10-mile race and 5K/10K options. Participants can enjoy a fun and festive atmosphere while supporting the charity partner, Growing Home, which focuses on breaking the cycle of poverty for families in..

Dirt Circus - Boulder is a vibrant community running event scheduled for August 9, 2025, in Boulder, Colorado. Organized by UltraSignup, this festival celebrates local races, run clubs, and businesses, fostering camaraderie among trail running enthusiasts. Participants can enjoy a social run with op..

The Into the Hills Eltuck 10K is part of a series of midweek trail races held at Lory State Park in Bellvue, Colorado. Scheduled for August 12, 2025, this event is designed to cater to both novice and experienced trail runners, offering a challenging course with significant elevation gain and stunni..

The Leadville Trail 100 Mile Run, known as the "Race Across the Sky," is a prestigious ultramarathon held annually in Leadville, Colorado. Established in 1983, this grueling race challenges participants with a 100-mile out-and-back course that features extreme elevation changes, including a peak at..

The Into the Hills Eltuck 5K is part of a series of midweek trail races held at Lory State Park in Bellvue, Colorado. Scheduled for August 19, 2025, this event features a challenging course with a steep climb and descent, making it suitable for both novice and experienced trail runners. Participants..

The NoCo Urban Ultra & Relay is a long-distance running event taking place on August 22-23, 2025, along the scenic Poudre River Trail in Northern Colorado. Participants can choose from a 50-mile solo race, a 100-mile solo race, or relay options for both distances, accommodating teams of 2 to 8 runne..

The Arrowhead Half Marathon and 5K is a scenic running event held in Arrowhead, Colorado, featuring a challenging half marathon course with approximately 3,000 feet of elevation gain over 13 miles. Participants traverse beautiful trails across Arrowhead, Bachelor Gulch, and Beaver Creek Ski Resorts...

The Byers Peak Stampede Half Marathon & 5K Run is an exciting running event set in the stunning Rocky Mountains, just 60 miles from Denver. Scheduled for August 23, 2025, the event features a challenging half marathon and a 5K, catering to athletes of all levels. The courses primarily traverse dirt..

The Staunton Rocks! Marathon and Half Marathon, scheduled for August 23, 2025, takes place in the scenic Staunton State Park, located in Colorado's Front Range Mountains. This event features a challenging yet accessible course, primarily on singletrack trails, allowing participants to enjoy breathta..

The Westminster Night Trail is an annual nighttime running event held at Standley Lake in Westminster, Colorado. Celebrating its 12th year, the race offers distances from 5K to 50K, all on scenic, packed dirt trails illuminated by lights and the stars. Participants enjoy stunning views of the lake a..

The Continental Divide Trail Run is a trail racing event held in Steamboat Springs, Colorado, on August 23, 2025. It offers three race distances: a 5-mile, a 16-mile, and a 50K ultramarathon. The courses feature scenic views of aspen and pine forests, with significant elevation gains—over 3,500 feet..

The Eltuck Valley 12K is part of the Lory Summer Trail Series, taking place at Lory State Park in Bellvue, Colorado. This event features a series of midweek trail races designed for both novice and experienced runners, offering distances from 5K to 12K. The series aims to provide a fun and low-key a..

The Front Range Ultra Dayze is a multi-day ultra-running festival held in Loveland, Colorado, from August 28 to September 1, 2025. It offers a variety of ultra-distance races, including timed events ranging from 12 to 100 hours and distance-based races such as 200-mile and 100-mile runs. The event f..

The Rock Hawk Trail Races will take place in Castle Rock on Saturday 30 August 2025. You can run between 5 and 50 kilometers.

The 10k @ 10,000 Feet is a renowned trail running event held in Steamboat Springs, Colorado, celebrated for its stunning mountain scenery. This challenging race features a 10k course, which is actually 6.8 miles, and a 5k option, both starting at the summit of Rabbit Ears Pass. Participants navigate..

The American Heroes Run is a commemorative running event held in Longmont, Colorado, designed to honor the heroes of 9/11 and celebrate patriotism. Participants can choose from various race distances, including a 100-mile run, marathon, half-marathon, 9.11-mile run, and a 5K, all set on a scenic 1.0..

The Black Squirrel Half Marathon, scheduled for September 6, 2025, takes place in Lory State Park, Bellvue, Colorado. This challenging 13.5-mile trail race features a mix of technical and non-technical terrain, with approximately 2,000 feet of elevation gain. Runners will enjoy stunning views of Hor..