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Armstrong Spiro Loop



9.0 mile 14.5 kilometer loop
90% Runnable


Ascent: 1,519' 463 m
Descent: -1,552' -473 m
High: 8,428' 2,569 m
Low: 6,930' 2,112 m


Avg Grade: 6% (4°)
Max Grade: 20% (11°)


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Trail shared by Megan W

This enjoyable loop has good views and proves a do-able challenge in one neat package.

Megan W

Features Views · Wildflowers

Mountain bikers may only bike uphill on the Armstrong part of this trail. Other users may use any park of this loop in either direction.


By combining the gentler uphill of the Armstrong Trail with the scenic Spiro Trail for the downhill, you've created the best of both worlds.

Runner Notes

Good packed surface, only a couple of rocky sections.


The plan is to run up the Armstrong Trail, take Mid Mountain Trail south to the top of Spiro Trail and then descend Spiro Trail all the way to the starting point. To reach the start of the Armstrong Trail, either take the Silver Spur trail from the ski area base or head through the Silver Star and golf course neighborhood to where the Spiro Trail and Armstrong trails hit Crescent Road. The Armstrong Trail is a relatively new, multi-use trail. Its popularity is increasing because it helps spread out traffic on the mountain and improves users' experiences. Armstrong is a directional trail for bikers (uphill only) but runners can go up or down it.

Armstrong climbs at a remarkably constant, moderate grade that makes the uphill pretty enjoyable. To start, the trail contours around the hillside mostly shaded by aspen trees. After passing the base of the King Con chairlift, the serious switchbacking begins, although this ascent feels gentler than ascending the Spiro Trail.

Armstrong ends at the junction with Mid Mountain Trail. Take the Mid Mountain Trail uphill for a couple more short switchbacks before it heads downhill, due south. If you find yourself traveling north (and entering the Canyons Ski Resort) you've gone the wrong way. Contour around the hillside, gradually losing elevation. Soon after the Motherlode chairlift appears on your left (to the east), be watching for the junction with the Spiro Trail.

Take the Spiro Trail downhill on a somewhat steeper descent. The trail itself is a lovely trek at a consistent grade through aspens and clumps of wildflowers. You'll cross many ski runs, and part of the navigational enjoyment is to orient yourself to where you ski in the winter months. The switchbacking of the trail increases at the bottom, providing more views of the Park City area. End this loop run at the Crescent Road trail access or head back on Silver Spur to reach the Park City ski resort base.

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May 5, 2018
Kathryn Baum
Was still a bit of snow to wade through, but was a great route overall! Trail was mostly marked well (couldn't find the entrance to Spiro at first). 9.9mi
Sep 10, 2017
Chase Tharp
Nice trail, spiro was the lesser portion. Took it easy but the trail is easily runnable. 9.2mi

Trail Ratings

  3.9 from 7 votes


in Park City


  3.9 from 7 votes
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28 Views Last Month
3,379 Since Mar 18, 2015



Views from the intersection of Armstrong and Ham Trails
Mar 18, 2015 near Park City, UT


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