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Ptarmigan Trail (#35)



13.2 mile 21.3 kilometer out and back
77% Runnable


Ascent: 3,536' 1,078 m
Descent: -3,536' -1,078 m
High: 12,489' 3,807 m
Low: 9,116' 2,779 m


Avg Grade: 10% (6°)
Max Grade: 34% (19°)


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Trail shared by Chelsea Gribbin

A climb to the summit of Ptarmigan Mountain

Chelsea Gribbin

Features Fall Colors · Views · Wildflowers


There are two ways to access Ptarmigan Trail, one is by Angler Mountain Trail and the other is starting from the Ptarmigan Trailhead up above the highway. If you start from the Ptarmigan Trailhead it is slightly longer but beautiful nonetheless.

Runner Notes

If there is any chance of thunder and lightning do not attempt to summit Ptarmigan. Once you a get a couple miles above treeline there is nowhere to take cover.


It starts with a steep climb crossing a residential road and then through a large meadow. Just before you hit the one mile mark, you'll enter into the trees and descend for about 1/4 of a mile before the powerlines. Cross under the powerlines back into thicker forest and there you'll find the trail begins to ascend again.

After a couple of miles, you'll pass Angler Mountain Trail on your right intersecting with Ptarmigan Trail. A half mile after this junction is a bench that overlooks the Gore Range on your left. This is a nice turning around point if you want a shorter run. But, if you are ready to summit, continue on up around the next corner. This is where it starts to get steep, but the trail is still nice for running. The switchbacks start at this point, they are gradual, for the most part. Around mile 4.5 you'll arrive at treeline. Continue straight up the trail, and you'll reach an intersection with Ptarmigan Pass Trail and Ptarmigan Peak Trail. Continue straight on Ptarmigan Peak Trail. Another mile and you'll reach the summit! Now for the fun part, turn around and run back down to the car, making sure to stay left at the Angler Mountain Trail intersection.

Flora & Fauna

Many wildflowers, Pika and maybe a marmot or two towards the summit!

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Sep 23, 2018
jt d
Jun 18, 2017
Joseph Mutter
Jun 11, 2017
Aaron Stewart
Lots of downed trees and a few snowfields 12mi

Trail Ratings

  4.5 from 15 votes


  4.5 from 15 votes
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in Colorado


78 Views Last Month
14,497 Since Mar 14, 2015



From the bench on Angler Mountain Trail looking south
Mar 14, 2015 near Silvert…, CO
Looking south towards Dillon Reservoir at what I just ran up.
Mar 14, 2015 near Silvert…, CO
Lovely aspen forest after the initial difficult, steep stretch of trail
Jul 19, 2015 near Silvert…, CO
Looking east over a snowfield in August - Ptarmigan Mountain Trail
Mar 14, 2015 near Silvert…, CO
The view from treeline is remarkable.
Jul 19, 2015 near Silvert…, CO
A lovely display of Rocky Mountain Columbine - our state flower.
Jul 19, 2015 near Silvert…, CO


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