Trail Running calendar near Longmont 2025-2026

The Midsummers Night Run is a 10K race held in Winter Park, Colorado, starting and finishing at the base of Winter Park Resort. The course features a mix of gravel roads and trails with an elevation gain of approximately 570 feet, offering a scenic and moderately challenging route. This event is par..

The Timberview Trail Run is an annual trail running event held at Lory State Park in Bellvue, Colorado. Celebrating its sixth year in 2025, the race offers three distances: 5K, 5 mile, and 10 mile, catering to all levels from beginners to experienced trail runners. The scenic courses feature foothil..

Chase the Moon is a unique overnight ultramarathon held in Highlands Ranch, Colorado, featuring a 12-hour solo and team relay format under the full moon. The event offers various distances including 12-hour solo, 3- and 5-person relays, 6-hour and 3-hour solos, and a 50K race. Runners traverse a sce..

The Silverheels Trail Runs, hosted by the Human Potential Running Series, is a premier ultra running event held in Como, Colorado, at an average elevation above 10,000 feet. The event features multiple distances including 10-Mile, 19-Mile, 60k, 50-Mile, 100k, and 100-Mile races, with the 100-Mile an..

The Never Summer 100km & 60km is a challenging mountain trail race held in State Forest State Park near Cameron Pass, Colorado. The event features two distances: a 100km (64.4 miles) with 14,500 feet of elevation gain and a 60km (36.6 miles) with 8,100 feet of gain. The course traverses rugged alpin..

The Elevation Run/Walk is an annual running event held in Conifer, Colorado, set at an average elevation of 8,200 feet. Celebrating its 13th year in 2025, the race features a 10K, a USATF-certified 5K, and a 2-mile fun run. The scenic course winds through Aspen Park neighborhoods and Meyer Ranch Par..

The Summit 200 is a challenging 200-mile mountain ultramarathon held in Summit County, Colorado. The race features a single 200-mile loop traversing stunning hiking trails, recreation paths, forest roads, and some pavement, with elevations ranging from over 9,000 feet to peaks near 12,800 feet. Runn..

The Boulder Rez Marathon, held at Boulder Reservoir in Boulder, Colorado, offers a scenic and mostly flat course with only 200 feet of elevation gain. Runners enjoy trails and dirt roads alongside the reservoir, with stunning views of the water and the Rocky Mountains. The event features multiple di..

The Lory Summer Trail Series is a welcoming midweek trail running event held every Tuesday in August at Lory State Park, Fort Collins, Colorado. It features four races with distances ranging from 5K to 12K, designed to accommodate both new trail runners and experienced racers seeking to improve spee..

The Eltuck Valley 5K is a trail running event held at Lory State Park in Bellvue, Colorado. Scheduled for August 5, 2025, it is the first race in a four-race midweek summer trail series designed for both new and experienced trail runners. The 5K course is noted for being the fastest and flattest of..

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..

The Run the Rockies Trail Race is held in Frisco, Colorado, featuring 5k, 10k, and half marathon distances. The courses traverse the scenic Frisco Peninsula trails, offering stunning views of Dillon Reservoir and the Ten Mile Range. Starting and finishing at the Frisco Nordic Center, the race includ..

Dirt Circus - Boulder is a free community running event held in Boulder, Colorado, celebrating local trail running culture. Organized by UltraSignup, this one-day festival features a social group run with options of a casual 4.5-mile or 10K route through local trails. The event fosters camaraderie a..

The Into the Hills Eltuck 10K is a challenging trail race held at Lory State Park in Bellvue, Colorado. Part of a four-race summer trail series, this event features the hilliest course with a 1,700-foot elevation gain, offering runners stunning mountain scenery. Designed for both new and experienced..

The Into the Hills Eltuck 5K is a midweek trail race held at Lory State Park, Bellvue, Colorado. Part of a four-race summer series, this event features a challenging course with a steep, quick climb and descent along the Homestead, Well Gulch, and Kimmons loop, offering about 700 feet of elevation g..

The NoCo Urban Ultra & Relay is a long-distance running event held along the scenic Poudre River Trail in Northern Colorado, passing through Fort Collins, Timnath, Windsor, and Greeley. The race offers 50-mile and 100-mile distances for both solo runners and relay teams, with the 100-mile race stage..

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 Staunton Rocks! Marathon & Half is a trail running event held at Staunton State Park in Pine, Colorado, featuring a marathon (26.3 miles, 4,500 ft elevation gain) and a half marathon (13.1 miles, 2,200 ft gain). The course is primarily singletrack (90%) with some dirt roads, set at high elevatio..

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..

The Antelope Dash is a trail running event held at Curt Gowdy State Park near Cheyenne, Wyoming. It features 4-mile and 8-mile races that traverse rolling hills and winding trails through a scenic landscape of aspens, pines, reservoirs, streams, granite rock formations, and hoodoos. The course start..