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blue Marshall Gulch To Aspen Loop

  4.3 ( 13 ) Favorite


3.8 mile 6.1 kilometer loop
83% Runnable


Ascent: 814' 248 m
Descent: -831' -253 m
High: 8,153' 2,485 m
Low: 7,433' 2,266 m


Avg Grade: 8% (5°)
Max Grade: 33% (18°)


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Trail shared by Nick Wilder

Experience an alpine escape near the summit of Mt. Lemmon.

Nick Wilder

Features Fall Colors · River/Creek · Views


A lovely creek, big views over Tucson (and the entire Mt. Lemmon area), an aspen forest, and cool temps make this a great run on a summer day. Starting on Marshall Gulch Trail #3, run up a gentle grade in deep shade next to a creek—even the hotter days are more comfortable here than on most other trails. The terrain is easy to navigate with only a few rocky sections, although it's a very popular area so you'll likely encounter a lot of other trail users.

Need to Know

This loop is great in either direction, but Lower Aspen Trail #93 is significantly steeper, so the direction shown (starting on Marshall Gulch Trail #3) makes for an easier climb.

Runner Notes

Parts of the Lower Aspen Trail #93 are too steep to run. Most of the rest of this is very enjoyable though. The altitude will take a big toll!


Starting from the Marshall Gulch Picnic Area, head up the singletrack path just to the right (north) of the bathrooms. Watch out for some poison ivy near the trailhead. There is a creek nearby, and, depending upon the time of year, you'll have a few wet areas to navigate. While it gains over 500 feet in just over a mile and a quarter, it's never steep in any one spot, so it's a comfortable climb to Marshall Saddle.

From the saddle, take a left (south) on Lower Aspen Trail #93. Continue running uphill (more than you might have guessed) through pine forests. Pass over a ridge with great views over Tucson before starting your descent down to the trailhead. Finally, you enter an aspen forest with a high density of very small aspen trees. The trail gets quite steep here, but it ends fairly quickly.

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Jul 2, 2019
Thomas Alcaraz
Was awesome
Aug 26, 2018
Marizonagirl M
Added additional Aspen Trail to fire tower at summit. 6.8 miles total

Trail Ratings

  4.3 from 13 votes


in Mt. Lemmon


  4.3 from 13 votes
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in Mt. Lemmon


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