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Sunnyside–Radio Tower



4.8 mile 7.7 kilometer out and back
72% Runnable


Ascent: 1,501' 458 m
Descent: -1,501' -458 m
High: 9,333' 2,845 m
Low: 7,845' 2,391 m


Avg Grade: 12% (7°)
Max Grade: 35% (19°)


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Trail shared by Seamus Crowley

The best out-and-back run high above the valley floor to see stunning views of Aspen and the surrounding Elk Mountains.

Seamus Crowley

Features Fall Colors · Views

No camping, no campfires.


A beautiful switchbacking run up the face of Red Mountain, providing stellar views of the valley below and the surrounding peaks the entire way up.

Need to Know

Little to no shade is available on the trail, so be prepared for sun and heat. Follow all trail signs to avoid ending up on bandit trails or private property.

Runner Notes

If running on the higher portions of the trail, be aware that it becomes fairly technical with multiple outcroppings of rocks jutting onto the trail.


The Sunnyside trailhead is directly off of McLain Flats Road, with a 10± vehicle parking lot on the opposite side of the road.

Starting with a relatively low grade, the trail grows steeper soon after beginning and is then a long, steady zig-zag climb to the finish, with the exception of a flat traverse of about a quarter mile. Obvious directional signage is present along the entire trail. The beginning of the trail has slight Aspen tree coverage, transitioning into low brush. Most people run only as far as the small radio tower, which is a natural stopping point in a quiet Aspen grove, before returning to the trailhead.

From the trail, there are sweeping views from Independence Pass to all four of the Aspen/Snowmass ski mountains and the high peaks in between. Be sure to bring your camera along so that you can make all of your friends jealous.

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Trail Ratings

  4.5 from 2 votes


in Aspen


  4.5 from 2 votes
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11 Views Last Month
1,170 Since May 26, 2017



A beautiful aspen grove stands near the top of the Sunnyside Trail.
May 26, 2017 near Aspen, CO
On a clear day, both Aspen and Independence Pass can be seen from the Sunnyside Trail.
May 26, 2017 near Aspen, CO
Enjoy great views from the Sunnyside Trail.
May 26, 2017 near Aspen, CO
The Sunnyside Trail is sure to give Fido a workout!
May 26, 2017 near Aspen, CO
The Sunnyside Trailhead is marked by this signpost and informative kiosk.
May 26, 2017 near Aspen, CO
A lower section of the Sunnyside Trail. The trail turns to red rock below the aspen groves.
Jun 6, 2017 near Aspen, CO


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