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greenBlue Keyhole Balloon

  3.9 ( 12 ) Favorite


2.3 mile 3.7 kilometer out and back
94% Runnable


Ascent: 256' 78 m
Descent: -257' -78 m
High: 5,314' 1,620 m
Low: 5,083' 1,549 m


Avg Grade: 4% (2°)
Max Grade: 14% (8°)


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Trail shared by Kayla Dome

An out and back run that loops around at a keyhole overlook of the mountains.

Kayla Dome

Features Birding · Views

Opens at sunrise and closes at sunset.


The entry trail at Devil's Backbone Open Space takes runners upward towards a picturesque overlook through a nautral keyhole in the rock. It looks out over the mountains with the highest peak visible being Longs Peak in Rocky Mountain National Park. This is great trail year round. 50% of the trail up to the Keyhole is for runners and hikers only.

Need to Know

Red-tail hawks and unique plants can be seen in this preserved land of Larimer County.


This trail starts at the Devil's Backbone Open Space parking lot. A gradual downhill through a secluded picnic area helps runners ramp up for the slight uphill for .7 miles. The dirt trail is well marked, and runners should take the Keyhole Loop Trail to the top without diverting to the right.

About a half a mile in, runners will come across a slightly rocky surface before returning to a smooth dirt path. It travels mostly uphill for .8 miles before a gradual down and up leading the Keyhole. The overlook is popular towards the end of the day with the great view overlooking the mountains west, so the trail can get a little busy. It is a relatively unknown trail though and mostly used by locals.

At the top of the Keyhole, travel north towards a small loop that takes runners back to the main trail to the parking lot. It is a very enjoyable route and one of my local go-to spots.

Flora & Fauna

There are lots of bees at the Keyhole overlook during the summer. Beware! As far as vegetation, there is a nature loop that points out some the local flora in the parking lot.

History & Background

The Devil's Backbone hogsback is one of the places in northern Colorado where you can see the ancient beach that once was part of this area. While that was 145 to 65 million years ago, the remnants of the Cretaceous period can be seen along the rock wall that is prominent to this area.


Land Manager: Larimer County, Colorado

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May 24, 2017
Kristina Ostrowski
Feb 17, 2017
Kayla Dome
60 degrees in February, I'll take it! Great run. 2.3mi — 0h 27m

Trail Ratings

  3.9 from 12 votes


  3.9 from 12 votes
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