Trail Running Calendar Colorado 2026-2027

Welcome to Colorado's premier trail running calendar for 2026-2027! Recognized as a trail runner's haven, Colorado seamlessly blends bustling urban settings with pristine mountain terrains. Whether you're a native, a newbie, or a visitor exploring the Centennial State's running trails, our calendar ensures you don't miss out on any event.

Denver, the renowned Mile High City, beckons runners with its urban-meets-nature charm. Iconic routes like the Cherry Creek Trail zigzag right through the city's pulse. Venturing south, Colorado Springs, dubbed the "Olympic City", boasts of trails skirting the monumental Garden of the Gods. Here, a run transcends the ordinary, offering an experience akin to striking gold.

For those seeking a quiet escape, Aurora presents peaceful reservoir paths, making urban detox achievable. If the allure of academic vibes mixed with nature captivates you, Fort Collins and its famous Horsetooth Reservoir trails won't disappoint. Meanwhile, Lakewood introduces runners to nature's canvas with the Red Rocks painting every run. And let's not forget Boulder, offering a diverse range of trails set against the stunning backdrop of the Flatirons.

Experience a focused trail run through the hills of Lory State Park with 1,700 feet of elevation gain. Enjoy a post-race social with pizza and beer in a scenic outdoor setting limited to 100 participants.

A four-race trail series on Tuesday evenings in August in Lory State Park. Distances include 5K, 10K, and 12K routes with varying elevation. Pizza and drinks follow each race, with series awards at the end.

A 100-mile mountain ultramarathon in Colorado's San Juan Range. The high-elevation course averages 10,000 feet with over 20,000 feet of climbing. It features a 38-hour cutoff and packet pickup in Durango.

Run along Boulder Reservoir on flat, mostly dirt trail courses with sweeping Rocky Mountain views. Choose from 10K, 3 4 marathon, half, full marathon or relay, with USATF certified courses, a shirt and a finisher medal.

Experience the first ever trail race through the iconic red rocks of Roxborough State Park. Tackle 50 miles or 50k of technical singletrack and high country terrain before enjoying a finish line celebration with food trucks and local brew.

Experience the trails of Cheyenne Mountain State Park with three race distances ranging from a 5K walk to a 25K mountain challenge. This chip timed fundraiser supports park conservation through scenic and high elevation courses.

Run the trails around Standley Lake in Westminster, Colorado. Choose from five distances, from a 5K to a 50K, on out-and-back dirt routes. Experience a cupless race with scenic views and a festive atmosphere.

Summit Grays and Torreys Peaks in this 8.8 mile Colorado endurance event. Participants must carry a 20lb dry load while tackling 4,101 feet of elevation gain.

Experience a classic backyard ultra format along the scenic Yampa River in Craig, Colorado. Complete 4.167 mile loops every hour until only one runner remains or enjoy a single lap in the Citizens Race.

Experience the historic Race Across the Sky in the Colorado Rockies. This legendary 100 mile ultramarathon features over 15,000 feet of elevation gain reaching heights of 12,626 feet.

Experience the high-altitude scenery of Leadville on this 10K course, which follows the first and final miles of the famous LT100 Run. With a single aid station and awards for top finishers, it's a classic mountain run. Registration is open..

Experience a hilly 5k trail race through the scenic Lory State Park. Enjoy a low key atmosphere followed by pizza, beverages, and a vintage race shirt in this midweek summer series event.

A four-race trail series on Tuesday evenings in August in Lory State Park. Distances include 5K, 10K, and 12K routes with varying elevation. Pizza and drinks follow each race, with series awards at the end.

Experience a high altitude trail run through the Rocky Mountains on 100 percent unpaved roads and trails. This dog friendly event in Fraser supports children facing cancer through the Shining Stars Foundation.

Experience high altitude trail running through the scenic singletrack and historic landmarks of Staunton State Park. Choose between a full or half marathon featuring sweeping mountain views and a festive post-race meal.

The Telluride Mountain Run is a technical mountain race in Colorado's San Juans, with routes reaching over 13,000 feet. Runners face rocky, exposed terrain on old mining roads and alpine tundra. This demanding event is not suited for beginn..

Experience high altitude trail running through the aspen groves and ski resorts of Arrowhead and Bachelor Gulch. Choose between a challenging half marathon with significant elevation gain or a scenic point to point downhill 5K.

Experience a fast and flat 12k trail race through the scenic Valley Trails of Lory State Park. Enjoy a low key atmosphere followed by pizza, beverages, and a vintage race shirt in Bellvue.

Experience the rolling trails and scenic views of Philip S. Miller Park in Castle Rock. With distances from 5K to 50K, this event offers well stocked aid stations and a supportive environment for all trail runners.

Experience trail running on the Continental Divide in Steamboat Springs. Choose from 50k, 16 mile, or 5 mile courses in a cupless event supporting local trails. Awards, finisher mugs, and a post-race taco bar await participants.