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Junco Lake Loop



22.2 mile 35.8 kilometer point to point
80% Runnable


Ascent: 4,972' 1,515 m
Descent: -4,962' -1,513 m
High: 12,049' 3,673 m
Low: 9,684' 2,952 m


Avg Grade: 8% (5°)
Max Grade: 44% (24°)


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Trail shared by Michael Tevebaugh

A challenging loop, technical in spots, but rewarding with valley views and countless alpine lakes.

Michael Tevebaugh

Features Lake · Views · Wildflowers · Wildlife


This is a great long run that will give you outstanding views of the Fraser valley, an up close look at Devil's Thumb, and innumerable alpine lakes. There is some exposure on the way down from Caribou Pass Trail but nothing too bad! Even people afraid of heights will not have a problem.

Need to Know

Arapaho National Forest costs $5 per day. There is a pay station that accepts credit cards (?!) that you'll pass on your way to Meadow Creek Reservoir. You can also pay the volunteer at Junco Lake in cash; however, there are usually only volunteers on the weekends.

A CAMPING PERMIT is required between June 1st and September 15th; pass waived for wilderness overnight campers with Indian Peaks Pass. Many of the lakes close to the trail have designated campsites that you should try to use rather than making your own new campsite elsewhere.


Begin at the Junco Lake Trailhead, in the Arapaho National Forest. Run on the Columbine Trail before arriving at the High Lonesome Trail about 0.25 miles from the Junco Lake Trailhead.

High Lonesome will take you through forest and some small rolling hills; a great warm-up before the first big hill!

After 5-6 miles, you'll take a left to continue on High Lonesome (which is also the CDT) for a very steep climb over the next 2 to 3 miles.

Upon reaching Devil's Thumb, take the ridge on your right and look out for cairns. The trail should be obvious. You'll take this until reaching Devil's Thumb Trail #902, which will take you to the east side of the Continental Divide. Once on the east side, you'll head on a steep downhill past several alpine lakes.

Continue on Devil's Thumb Trail until reaching Diamond Lake Trail on your left. Diamond Lake will climb until eventually flattening out at Diamond Lake.

After you get to the lake, you'll head downhill, crossing several streams, until reaching the Arapaho Pass Trail on your left.

Arapahoe Pass is a steady but not-too-steep climb. At the top, you'll switch over to Caribou Pass Trail and have awesome views of the valley and alpine lakes below.

You'll continue on Caribou Pass Trail, all downhill, until you reach a junction with the Columbine Trail, and head back to the parking lot.

Flora & Fauna

Lots of wildflowers in the summer!

History & Background

There is some cool mining equipment about halfway up the Arapaho Pass Trail!

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Sep 13, 2019
Atsuko Ohtake
did this CCW starting at Devils Thumb trailhead. It was about 24 miles. Beautiful!
Aug 26, 2019
Started from Fourth of July TH. Linked up with High Lonesome Loop. 31.5mi
Jul 30, 2019
Atsuko Ohtake
Started at Devils Thumb Trailhead and went counter clockwise. few snow patches to cross, but was stopped by icy patch in couloir descending down to 4
Jul 28, 2019
Scott Coburn
22.2mi — 5h 30m
Aug 22, 2018
Michael Reschly
Small sketchy stretches between Arapahoe and Caribou passes, but nothing that bad. Several moose along the western-most portion of the loop.

Trail Ratings

  4.5 from 6 votes


  4.5 from 6 votes
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in Colorado


86 Views Last Month
9,613 Since Aug 20, 2017



Flowery meadows on a rainy day.
Aug 1, 2017 near Nederland, CO
Looking toward Devil's Thumb Peak, yeah!
Aug 25, 2015 near Fraser, CO
Summer flowers were crazy epic.
Jul 10, 2016 near Nederland, CO
View from the top
Aug 23, 2019 near Fraser, CO
This panorama looks down to the valley/trailhead, and up toward Arapahoe Pass.
Jul 4, 2017 near Nederland, CO
Views to the east just prior to heading down on the Devil's Thumb Trail (taking loop clockwise)
Sep 28, 2018 near Fraser, CO


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