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Colorado Trail Running: A Pace All Its Own


There’s running, and then there’s trail running in Colorado.

Ranging from wide and flat to steep, rocky and heavily forested, Colorado trails present runners with fresh challenges and incredible scenery with every new step. But transitioning to trails means totally rethinking the way you run — from settling into slower paces to constantly scanning the ground for rocks, tree roots and other natural obstacles that can bring you down if you’re not paying attention.

Just ask Clare Gallagher. A former Princeton track runner-turned-professional ultramarathon runner, Clare Gallagher first fell in love with trail racing while living in Thailand. After moving back to her native Colorado, she ran the second-fastest women’s time ever at the grueling Leadville Trail 100 — but not before enduring some bumps in the road as she learned her way around our state’s demanding (and rewarding) trails.

Here, Gallagher talks about the joys and challenges of trail running in Colorado, and tells us about her favorite place to run: Green Mountain.

What: Green Mountain, Boulder’s “local mountain”
Where: Chautauqua Trailhead, Boulder, Colorado
When: Year-round (it may be icy in winter, so bring micro-spikes, yaktrax and/or poles)
Why: To feel amazing and get great Front Range views
Who: Locals and visitors alike

When I first moved to Boulder, I thought I had a good idea of what an everyday trail run looked like. I quickly learned there’s no such thing. Unlike the collegiate running regime I’d come from (think 8 miles in one hour), there is no standard hour-long run on the trail. It could be 4 miles. It could be 8 miles. It could be a 30-minute run that covers 1.5 miles. One thing is certain: Colorado trails don’t care about your pace!

I came to Boulder after spending most of the past two years living in southern Thailand post-college, teaching English and leading a youth swim and environmental program. It was in Thailand where I ran my first trail race and ultramarathon, and in Thailand (of all places) where I got hooked on dirt, addicted to vert — shorthand for vertical gain — and hungry for competition.

Moving to Boulder was an obvious choice for me. It’s laden with trail runners, and I grew up a stone’s throw away in Englewood. I started a job scribing in emergency rooms in order to apply to medical school; little did I know that Boulder would be the canvas not for my medical career, but for my full-time career in trail running. 

This isn’t to say that I was a professional runner on day one. From my downtown apartment, I had two miles of uphill pavement to get to Boulder’s loading dock of trails: the Chautauqua area. On my first run to Chautauqua, I hopped onto a trail that looked pleasant and just kept going. I asked an elderly man with hiking poles, “What trail is this?”

He kindly answered: “Gregory Canyon Trail. You know, it goes to the top of Green Mountain. Lots of you runners do this all the time. Why don’t you go to the top?”

I went up a mile or two more, only to turn back due to a time constraint. I yelled to the man as I passed him coming down, “Thanks for the tip, I’ll summit another day!”

When I got home, I was astonished at how few miles I’d run in two hours. Welcome to Colorado trail running.

The following week I joined my first group trail run, which went to none other than Green Mountain. The group, Rocky Mountain Runners, summits Green every Monday night from Chautauqua, rain or shine. It took about two hours, as they have a strict “no-drop rule,” which means waiting for the back of the pack at certain trail junctions. I made some of my best friends on those first Green Mountain group runs. And I now summit almost every time I start up Gregory Canyon Trail.

Reaching the summit via Ranger Trail and looking at all of the sparkling Front Range — including Denver — at just over 8,000 feet in the darkness is spectacular. And it’s equally memorable during the day. Really, any time you summit Green it’s outstanding. You just have to do it.

The Route
Now it’s your turn.

The standard counter-clockwise route follows: Gregory Canyon Trail up to Ranger Trail to the summit. Coming down, take E.M. Greenman to Saddle Trail to Amphitheater Trail back to the Chautauqua parking lot. This loop is just over 6 miles with 2,500 feet of vertical gain. It can take a seasoned pro under an hour, and a hiker three to four hours.

Technically, you summit above and behind the Flatirons. It’s sneaky, because you cannot see it from the Chautauqua trailhead, or when looking west at the Boulder skyline. Green’s neighboring mountains are Bear Peak, which is a longer, steeper journey, and Flagstaff Mountain, which has an identically named paved road that leads to the summit plateau.

Make Green your go-to if you’re visiting Boulder for a morning, afternoon or evening — just don’t forget a headlamp! You will feel like a local. (Or, at least feel out of breath and motivated to get back on your daily exercise program!)

Explore Boulder Before or After Summiting Green Mountain
Make time to visit a few of Clare’s favorite spots in the Boulder area.

Trident Café. Boulder’s oldest bookstore and a great coffee spot, located on the west end of downtown. (Temporary closed.)
Neptune Mountaineering Cafe. South Boulder’s newest coffee shop, connected to the iconic mountaineering store.

Patagonia if you need supplies (like warm gloves when the summit of Green is windy!). Located on the Pearl Street Mall.

Eat in Downtown Boulder

Zeal for scrumptious Asian fusion bowls with spicy Diablo sauce. Very vegan and gluten-free friendly.
Sherpa for authentic Nepalese and Indian food.

Learn more about Clare >>

Check out Colorado extreme races, hiking trails and other outdoor activities.

Photo credit: Brendan Davis