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Sunnyside Trail



5.4 mile 8.8 kilometer point to point
79% Runnable


Ascent: 2,380' 725 m
Descent: -241' -73 m
High: 10,087' 3,075 m
Low: 7,846' 2,392 m


Avg Grade: 9% (5°)
Max Grade: 39% (21°)


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Trail shared by Seamus Crowley

A beautiful and rewarding trail up Red Mountain with stunning views of the valley below and Elk Mountain Range peaks.

Seamus Crowley

Features Fall Colors · Views

No camping, no campfires.

Runner Notes

If running on the portions of the trail below the radio tower, 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 the beginning and is then a long, steady zig-zag climb toward the top of the mountain, 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. Eventually, the trail passes a small radio tower, which sits among a quiet Aspen grove at the top of the major switchbacks on Red Mountain. The most difficult portion of the trail, in terms of elevation gain and steepness, exists from the trailhead to this point at the radio tower.

Moving further along the trail, signs appear for the Shadyside Trail and in order to stay on the Sunnyside Trail, keep to the right. The Sunnyside Trail traverses across the face of the Red Mountain before reaching another intersection with the Shadyside Trail, at which point one should once again stay to the right. The trail continues along through dense forest before concluding at its intersection with Repeater Road. At this point, it is possible to follow Repeater Road as a connector to other trail systems in the area.

From the trail, particularly below the radio tower, 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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May 26, 2019
James Tasca

Trail Ratings

  4.5 from 2 votes


in Aspen


  4.5 from 2 votes
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105 Views Last Month
3,183 Since Jun 2, 2017



View from Red Mountain, traversing its face on the Sunnyside Trail.
Jun 6, 2017 near Aspen, CO
A beautiful aspen grove stands near the top of the Sunnyside Trail.
May 26, 2017 near Aspen, CO
Enjoy great views from 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
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


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