Trail Running calendar near Longmont 2025-2026

The Timberview Trail Run is an exciting annual event held at Lory State Park in Colorado, featuring three race distances: a 10-mile, a 5-mile, and a 5K trail run. Scheduled for June 28, 2025, this event welcomes participants of all ages and skill levels, making it ideal for beginners and seasoned ru..

Chase the Moon is an exciting 12-hour endurance running event taking place in the Highlands Ranch Backcountry trail system. Participants can choose to run solo or form teams of three or five for a relay. The race begins at sunset and continues through the night, illuminated by the full moon, offerin..

The Silverheels Trail Runs, part of the Human Potential Running Series, will take place on July 11-12, 2025, in Como, Colorado. This annual event features multiple race distances, including a 100-Mile, 100k, 50-Mile, 60k, 19-Mile, and 10-Mile, catering to a range of runners. The course, set at an av..

The Never Summer 100km and 60km races will take place from July 25-27, 2025, in the scenic State Forest State Park, Colorado. Participants can choose between a challenging 100km course with a total elevation gain of approximately 14,450 feet or a 60km course with about 8,850 feet of elevation gain. ..

The Summit 200 is an extraordinary 200-mile mountain race set in Summit County, Colorado, featuring a challenging loop that showcases stunning hiking trails, forest roads, and scenic views. Participants will experience significant elevation changes, with the lowest point over 9,000 feet and sections..

The Boulder Rez Marathon is a scenic running event held at the Boulder Reservoir in Boulder, Colorado. Scheduled for August 2, 2025, the marathon features a flat course primarily on dirt roads and trails, offering stunning views of the reservoir and the Rocky Mountains. Participants can choose from ..

The Lory Summer Trail Series, taking place from August 5 to August 26, 2025, offers a series of midweek trail races at Lory State Park in Fort Collins, Colorado. Participants can choose from distances of 5K, 10K, and 12K, designed to cater to both novice and experienced runners. The event aims to cr..

The Eltuck Valley 5K is a part of a fun summer trail race series held at Lory State Park in Bellvue, Colorado. This event is designed for both novice and experienced runners, offering a flat and fast course that serves as the first race in the series. Participants can enjoy a friendly atmosphere, wi..

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 ..

The Into the Hills Eltuck 10K is part of a fun summer trail race series held at Lory State Park in Bellvue, Colorado. Scheduled for August 12, 2025, this event features a challenging 10K course with a significant elevation gain of 1,700 feet, making it the hilliest race in the series. The series aim..

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. This inaugural event, organized by ..

The Westminster Night Trail, celebrating its 12th year, invites runners to experience a unique nighttime race around Standley Lake in Westminster, CO. Participants can choose from various distances, including 50K, 35K, Half Marathon, 10K, and 5K, all set against the stunning backdrop of Colorado's n..

The Staunton Rocks! Marathon and Half Marathon, scheduled for August 23, 2025, is a premier trail running event held in Staunton State Park, Colorado. Designed by trail runners for trail runners, the event features a challenging yet accessible course that showcases the park's stunning landscapes, in..

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

The Front Range Ultra Dayze is an exciting ultra-running event taking place in Loveland, Colorado, from August 28 to September 1, 2025. This festival features a variety of ultra-distance races, including 200-mile, 100-mile, and timed events ranging from 12 to 100 hours. Participants can camp at the ..

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

Devil on the Divide is a challenging trail running event held in Empire, Colorado, featuring two race distances: a 50K and a 22K. Participants will experience breathtaking views of Clear Creek County and the Continental Divide, with the 50K course reaching altitudes over 13,000 feet and climbing mor..

The Cirque Series - Arapahoe Basin is a challenging mountain running event set in Keystone, Colorado, featuring a 9.2-mile course with an elevation gain of 2,411 feet. Participants start at 10,780 feet and navigate through scenic trails, including the High Noon parking lot and Black Mountain Lodge, ..

The HRCA Wildcat Mountain Trail Races, scheduled for September 6, 2025, in Littleton, Colorado, features a variety of events including a 10-mile race, a 10K, and a Kid's Race. The races start at the Douglas County East/West trailhead and traverse the scenic HRCA Backcountry Wilderness Area. Particip..