Five Loops to Run Through Colorado’s Autumn Colors

runner in colorado aspen grove fall autumn leaves

Trail running in the fall is the perfect way to experience the changing of the seasons and frolick through the leaves. We’ve put together this list of favorites for getting in some long miles in the colors before the snow starts to fall. Make the most out of those autumn afternoons, and grab a pumpkin pie on your way back to town!

Four Pass Loop

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Nestled in the Maroon Bells Wilderness between Aspen and Crested Butte, CO, this 28 mile route is enveloped in aspen groves, brightly colored scrub brush, and contrasted by mountains of vibrant red rock. Let’s not forget those blue alpine lakes!

360°VR Tour of Four Pass Loop

High Lonesome Loop

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Another loop close to Boulder, this 16 mile loop trail passes some aspen groves and a few alpine lakes on its way to the Continental Divide. Watch the mountains rise up across the valley beside you as you climb skyward through the colors. 

Alcove Spring to Syncline Loop


This one isn’t in Colorado, but we had to include it anyway. Take a weekend trip to Canyonlands National Park to get on this remote and sparsely traveled 20-ish mile loop. There’s not many aspen, but the scrub brush in the area and the foliage along the Green River is changing, and, when contrasted with the red of the desert, the aqua blue sky, and pleasantly crisp desert air, this loop will make you wonder how you didn’t know about it sooner.

Note: there is NO water access on this loop, and if you find any, you’ll absolutely need a filter. Speaking from experience.


Pawnee Buchanan Loop


Close to Boulder, CO, this 27 mile loop starts near the popular Brainard Lake Trailhead and crosses over Buchanan Pass and Pawnee Pass. It quickly leaves the hustle and bustle of the park and gets you into the solitude of the backcountry. Cross over Buchanan pass, many waterfalls, and Pawnee Lake, and the finale climb up the rocky and sharp Pawnee Pass. Definitely a classic. 


Kenosha Georgia Pass Loop

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Kenosha Pass is one of Colorado’s largest aspen groves, and the whole skyline here pops yellow if you are lucky. Also, lucky for you, the Colorado trail passes right through here and winds up above treeline before hooking the West Jefferson Trail back down through more aspens and to the start.


We’ve barely scratched the surface of the many magnificent loops in Colorado (and Utah)! What are your suggestions? Leave a comment below!

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Four Pass Loop

Just outside the mountain town of Aspen, Colorado lies one of the pinnacle trail running experiences in Colorado: The Four Pass Loop. Enveloped by flowered tundra, alpine lakes, jagged peaks, lush grasses, streams, and every color in the spectrum, this giant loop takes you for a ride, as its name claims, over four separate mountain passes.

Leadville 100 Mile

Rich with mining history, the Race Across the Sky is one of America’s original 100 milers and one of the most competitive. Bring your high-altitude lungs!

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