Trail Running calendar near Boulder 2026-2027

Join the USCSA Cross Country Ski Racing Festival at Snow Mountain Ranch in Granby Colorado on Jan 24 and 25 2026. Collegiate teams and middle and high school racers take on classic distances and a skate sprint over two action packed days.

The Freakin Freezin 5K - Denver will take place in Civic Center on Sunday 25 January 2026. You can run 5 kilometers.

The Sourdough Snowshoe Race in Nederland, CO is a donation based backcountry event offering 18K and 30K routes where snowshoes are required. Enjoy rugged alpine scenery with a warming tent and hot drinks at the finish.

Join the Super Sunday 5K on February 8, 2026 in Littleton for a scenic run along the Mary Carter Greenway. Celebrate at a post race party at Breckenridge Brewery Farmhouse with 20% off food and drinks and community fun.

A two-person partner race on Virginia Canyon road in Idaho Springs, CO, held on Valentine’s Day. Runners each complete a roughly 12-mile out-and-back; team time is the sum of both individual times and multiple awards are offered.

Race The Ranch is a snowshoe race at Snow Mountain Ranch near Granby, Colorado on April 4, 2026, offering 5k, 25k and 50k looped courses over scenic groomed and singletrack snow trails. Finishers receive a custom beanie and engraved Miir ca..

Join Run the Ranch April 10 and 11, 2026 at Sylvan Dale Guest Ranch in Loveland, Colorado for trail races on private ranch trails, from 5K and 10K to timed 4 hour, 6 hour and 12 hour solo and relay events. Virtual options available.

Mountain Ridge Trail Race on Saturday April 11 2026 in Highlands Ranch Colorado starts and finishes at Mountain Ridge Middle School. Choose 21 mile, half marathon, 10 km or 5 km on mostly dirt single track with rolling climbs.

Take on the scenic Poudre River Trail April 11 and 12 2026 in Northern Colorado with 50 and 100 mile solo and relay options. Stocked aid stations, finisher swag, belt buckles for solos and a lively post race party await.

Run the Greenland Trail Races in Larkspur, Colorado on May 2, 2026 with 50K, 25K, 8 Mile and 4 Mile options and the 2026 RRCA National 50K Championship. Scenic dirt trails wind through ponds, oak hills and offer Pikes Peak views.

Niwot's Challenge is a by invitation only endurance event near Sedalia, Colorado that prizes off trail navigation and self reliance over racing. Limited to 40 entrants, it offers routes up to 100 miles for experienced wilderness runners.

Take on Quad Rock 25 or 50 mile trail races through Lory State Park and Horsetooth Mountain Park near Fort Collins. Rugged singletrack, big climbs and full aid stations make this scenic loop a true mountain challenge.

Samson's Revenge at the YMCA of the Rockies in Estes Park offers 10k, 27k and 55k looped trail races with a steep climb to Bible Point. Enjoy flowing single track, on course aid and a custom Fractel hat plus wool finisher socks.

Run the North Fork 50 Ultras in Buffalo Creek, Colorado on May 30, 2026, with 50 mile and 50K options along scenic soft surface singletrack through ponderosa pine and granite. Enjoy challenging trails while supporting local nonprofits.

Hit alpine single track at Granby Ranch in Granby, Colorado on June 6, 2026 with options from 6 Mile to 50k and a unique Elevation Challenge. Expect rugged scenery, well stocked aid stations, and a lively resort finish.

The Great Divide Ultra is a weekend trail festival in Divide, Colorado, June 6-7, 2026, featuring 25k, 50k, 100k and 100 mile looped races through Mueller State Park with rolling meadows and Pikes Peak views. A Dark Divide Night Run adds ev..

A looped 10k+ trail run at Devils Backbone Open Space in Loveland, CO, marked with flour arrows and featuring a staffed water aid near mile three, old school timing with placement sticks, and a post-race awards gathering at Loveland Alework..

Scenic dirt trails around Barr Lake offer looped courses with continuous lake and front range views. Distances from 5K to 50K suit beginners to ultrarunners, with aid stations on longer routes and a cupless sustainability focus.

Join the Leadville Trail 100 Run Camp in Leadville, Colorado, June 19 to 21 for a three day preview of the LT100 course. Enjoy guided day and night runs, gear demos, shuttles and recovery services for a full race ready experience.

Race in the Clouds at Alma Cemetery Meadow offers high country trail running, mountain bike races and weekend camping at 10,600 feet. Choose from a trail half, 10K, multiple bike distances and free kids races for a weekend of alpine adventu..