A loop to the top of Boulder's most iconic mountain.


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Green Mountain is one of the three major summits outside Boulder, and the mountain that houses the famous Flatirons.

This trail run to its summit is a classic of the Boulder area and begins right from town.

Thanks to the large network of trails here, there are actually several routes to the top of Green Mountain.

This variation offers an ideal mix of scenery, difficulty, and ease of access.

It’s not the shortest, easiest, longest, nor hardest way to the summit.

Feel free to explore the trails and find your own favorite path. It begins from Gregory Canyon Trailhead, where parking is often full.

You may have to park farther away along Baseline Road or elsewhere in the neighborhoods.

Be prepared to pay for parking.

Baseline Trail can be used to start the run from Chautauqua Park. Gregory Canyon trail heads steadily uphill along a tumbling stream.

Most of this stretch is on rocky, sun-exposed slopes that can be very hot in summer.

Hang in there, and you’ll reach shade soon enough.

At a junction near Realization Point, Ranger Trail heads into much denser forest on north-facing slopes.

This trail delivers you to the summit of Green Mountain, but not easily.

Some sections are on loose or rocky natural surface, and others are on constructed stairs.

Eventually, the trail gains a ridgeline of the mountain where trees thin out, and you’ll find great views westward to the Rocky Mountains. Once you meet West Ridge Trail, you’re almost at the top.

Take a final few switchbacks to reach it, then catch your breath and drink in the views.

A rock outcrop makes the perfect conical summit to this mountain.

Scramble up it to peer over the trees and see in all directions.

The city of Boulder lies below to the east, and peaks on the Continental Divide span the horizon to the west. E.M.

Greenman Trail descends the other side to begin a relentless downhill and complete the loop.

Descending this way is shorter than returning the way you came, but that means it’s steeper.

Saddle Rock Trail even has a ladder in one spot for aid.

The whole way down is equally scenic, so try to stop and look up from your feet every now and then.

Amphitheater Trail is especially beautiful, passing beneath rock formations that resemble mini Flatirons. Though the Flatirons themselves aren’t visible anywhere from this route, you can enjoy the summit with the satisfaction that you sit above them, having exceeded their summits in elevation.

As you drive or walk away from the trailhead after completing the run, look over your shoulder to admire the impressive rock slabs and the greater mountain you just conquered. Sources: https://bouldercolorado.gov/osmp/gregory-canyon-trailhead http://www.beyondboulder.com/green-mountain https://www.summitpost.org/green-mountain/152442