Trail Running calendar near Boulder 2026-2027

Experience the Rocky Mountains at Granby Ranch Resort with distances ranging from 6 miles to a 14 hour elevation challenge. Runners navigate single track trails through aspen groves and alpine meadows with views of the mountain range.

Experience smooth single track trails and sweeping views of Pikes Peak at the Great Divide Ultra. Choose from distances ranging up to 100 miles on a scenic looped course through the meadows of Mueller State Park.

A multi-distance running festival at Luvin Arms Animal Sanctuary in Erie, CO, featuring looped off-road courses with mountain views, one central aid station, onsite parking, and races from 5k up to 50 miles plus 3hr/6hr/9hr/12hr timed event..

Experience a scenic loop course through the Devil’s Backbone Open Space in Loveland. This manual timed trail run features natural terrain and includes a commemorative hat for all participants.

A four race trail series at the Argo trails in Idaho Springs, Colorado, held June to September 2026. Each event is about 5 miles with 785 feet of gain on non technical, runnable trails with visual finish timing.

Looped trail races around Barr Lake in Brighton, Colorado, with five distances on 100 percent dirt and lake and Front Range views. Courses have low elevation gain per loop, designated aid stations on longer routes, and drop bag areas.

Prepare for the Race Across the Sky at this three day training camp in Leadville. Run key sections of the 100 mile course alongside veteran guides and attend educational panels on nutrition and biomechanics.

Experience up to three miles of messy fun at the Colorado National Speedway. Navigate obstacles by crawling wading and sliding through the mud with friends and family during this unique event in Dacono.

Celebrate the longest day of the year with a scenic trail run through Beaver Creek Resort. Enjoy blooming wildflowers and breathtaking mountain views across diverse single track and gravel courses.

Summer Vibes Bike Rally & Run Festival in Lyons Colorado pairs gravel and road bike rallies with trail running, relays, live music, recovery pools and camping for a combined endurance and festival weekend.

Experience the peaks of Colorado through a series of four half marathons and a 25 km trail race. Run through iconic locations like Estes Park and Nederland while supporting local youth programs.

A community-focused trail festival in Gold Hill, Colorado, with 28K, 12K, 5K and Kids 1K races, a shuttle from Boulder, and proceeds supporting wildfire preparedness for the town.

Experience the beauty of Lory State Park at this USATF sanctioned trail race featuring 5K, 5 mile, and 10 mile distances. Enjoy scenic foothill views, plant-based post-race pancakes, and unique wooden medals.

Experience the highest trail marathon in the USA reaching 13185 feet at Mosquito Pass. Choose between a 26.4 mile marathon or a 15.46 mile heavy half through Leadvilles historic mining district and rugged high altitude terrain.

An overnight endurance event in Highlands Ranch, Colorado offering solo and team relay options on a 10.3 miles dirt loop beneath a full moon. Two aid stations, drop bags, medical support and a headlamp requirement are provided.

A lap-based backyard ultra around Lake Estes in Estes Park, Colorado. Each lap is 4.252 miles on a paved bike trail with 150 feet of gain, repeated hourly until one runner remains; aid, a custom hat, and athlete village space are provided.

Experience a half marathon in the mountains of Nederland Colorado. This event features a significant elevation gain of 4226 feet with the summit always in view.

Kick off Independence Day with a 5k run/walk in Winter Park, Colorado. The scenic route travels along the Fraser River Trail and finishes at the Rendezvous Event Center for a post-race party.

A July 4 5 kilometer run or walk in downtown Leadville, with downtown bib pickup and an Independence Day parade afterward. Adult entry is $25 and youth 17 and under may enter for free, with proceeds supporting local youth athletics.

Celebrate 50 years of history at the Vail HillClimb, a 12.2 km mountain race gaining over 2,000 feet of elevation. Run from Vail Village to the scenic Mid-Vail finish line for incredible views and commemorative awards.