Trail Running calendar near Lone Tree 2025-2026

The Cheyenne Mountain Run, held at Cheyenne Mountain State Park in Colorado Springs, offers three trail race distances: 5K, 10K, and a challenging 25K to the mountain summit. The 25K course features a 3,450-foot elevation gain, ascending via Talon, North Talon, and Dixon Trails to about 9,450 feet,..

Leadville Trail 100 Run, presented by La Sportiva, is a legendary 100-mile ultramarathon held in Leadville, Colorado. The mostly forest-trail, out-and-back course climbs from about 9,200 feet to 12,600 feet on two major peaks, including Hope Pass, with rugged Colorado high-country terrain and notabl..

The Into the Hills Eltuck 5K is a midweek trail race held at Lory State Park in Bellvue, Colorado. Part of a summer trail 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 gai..

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. It features 50-mile and 100-mile races available for solo runners and relay teams, with the 100-mile race staged o..

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 primarily on dirt roads and trails with stunning mountain views. The half marathon starts at a..

The Westminster Night Trail in Westminster, Colorado, is a vibrant night trail running event held at Standley Lake. Celebrating its 12th year, it offers distances of 50K, 35K, half marathon, 10K, and 5K, all on 100% packed dirt trails featuring a mix of single-track and bike paths. Runners experienc..

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 an average el..

The Bluffs 8K Trail Run is a challenging race held at Bluffs Regional Park in Lone Tree, Colorado. The course features rolling hills and beautiful views, with a mix of fine crushed gravel and some rugged, steep sections. The race starts and finishes near the Prairie Sky Park parking lot.Participants..

The Eltuck Valley 12K is part of the Lory Summer Trail Series held at Lory State Park in Bellvue, Colorado. This midweek trail race series offers a range of distances from 5K to 12K, catering to both new and experienced trail runners. The August 26 race features a fast and flat 12K course along the..

Front Range Ultra Dayze is a Loveland, Colorado ultra-running festival staged at Centennial Park along the River’s Edge Natural Area, an epic ultra-running party. It features a mix of distance-based and timed events, including 200-mile, 100-mile and 50k races, plus 100-, 72-, 48-, 24- and 12-hour ti..

The Rock Hawk Trail Races take place at Philip S. Miller Park in Castle Rock, Colorado, featuring distances of 50K, 25K, 10K, and 5K. The event is held on the scenic, rolling trails of Miller Park and the Ridgeline Trail systems, offering a course that is not overly technical but still challenging a..

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

The American Heroes Run, held in Longmont, Colorado, is a patriotic running event commemorating the events of 9/11. It features a variety of distances including a 100-mile ultra with a 30-hour cutoff, a 24-hour run, marathon, half-marathon, 9.11-mile, and 5K races. The course is a flat, fast 1.05-mi..

The HRCA Wildcat Mountain Trail Races, held in Littleton, Colorado, offer a scenic and challenging trail running experience through the HRCA Backcountry Wilderness Area. Participants can choose from a 10-mile or 10-kilometer course, both featuring 100% dirt trails with varied terrain and stunning mo..

The Black Squirrel Half Marathon is a 13.5-mile trail race held in Lory State Park near Fort Collins, Colorado. Featuring approximately 2,000 feet of elevation gain and loss, the course offers a challenging yet accessible experience on mostly dirt singletrack trails with a mile of dirt road. Runners..

Devil on the Divide is a two-distance trail race in Empire, Colorado, offering 50K and 22K options. The course features dirt, largely single-track, point-to-point routes that reach elevations above 13,000 feet, with about 6,500 feet of climbing on the 50K and around 3,400 feet on the 22K. Celebrated..

Cirque Series returns to Arapahoe Basin, Colorado, for a high-alpine mountain race. On White River National Forest trails above Keystone, the course runs about 9 miles with roughly 2,411 feet of elevation gain, starting at Mountain Goat Plaza at the base of A-Basin. Racers ascend via summer road to..

NedNed Trail Fest in Nederland, Colorado, at 151 East Street, offers a trail half marathon (13.3 miles with 1,408 feet of elevation gain), a 10K (6.3 miles, 712 ft gain), and a 5K (family-friendly, leashed dogs allowed). Runners wind through Old Town Nederland on dirt roads and single-track trails a..

The Breckenridge Oktoberfest 5K is a festive trail run held in historic downtown Breckenridge, Colorado, as part of the annual Oktoberfest celebration. Scheduled for Saturday, September 13, 2025, the 5K course winds through the scenic Town of Breckenridge Trails, showcasing beautiful fall foliage an..

The Snow Mountain Ranch Trail Running Festival, held at the YMCA of the Rockies in Granby, Colorado, offers a scenic and challenging trail running experience with race distances of 50K, 33K, Half Marathon, 10K, and 5K. Set amidst rolling hills, golden aspen groves, and mountain vistas, the courses f..