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Four Pass Loop

 5.0 (96)

27.1 Miles 43.6 Kilometers



7,498' 2,285 m


-7,498' -2,285 m



Avg Grade (6°)


Max Grade (28°)

12,457' 3,797 m


9,569' 2,917 m


Shared By Jason Smith


All Clear 4 days ago
Dry: Great Fall colors! History

Getting forecast...

An all-time journey over four 12,500' alpine passes, circumnavigating the Maroon Bells.

Jason Smith

Dogs Leashed

Features Birding · Fall Colors · Lake · River/Creek · Views · Waterfall · Wildflowers · Wildlife

If you're planning on doing this as an overnight, you must perform a self check-in and fill out an overnight permit. For more information on camping, download this PDF.


Up and over four incredible 12,000'+ mountain passes around the Maroon Bells Wilderness. People do this as a 4-day backpack... and it's a common 1-day run!

Need to Know

To access the trailhead at Maroon Lake, you must enter the Maroon Bells Scenic Area before 8am or after 5pm to access with a vehicle, which a $10 entrance fee is required. Otherwise, shuttle buses run for all visitors arriving between 8am-5pm. For more info click here.


Begin at the Maroon Snowmass Trailhead. This route is described counterclockwise, going Buckskin Pass, Trail Rider Pass, Frigid Air Pass, West Maroon Pass. Either way is great.

Proceed South on Maroon Snowmass Trail, climbing gradually over 1.5 miles. Make a right at a signed T-intersection headed for Buckskin Pass (Buckskin Pass Trail). Nowhere to go but up with spectacular views of N. Maroon (14,014') blowing up to your left as you crest treeline.

From the top turn around to savor the early morning sun on Pyramid Peak (14,018'), eye up the trail descending right and take it down toward the densely forested Snowmass Creek drainage. After about 3 miles from the top of Buckskin, take the first left onto Geneva Lake Trail at a t-intersection. In early August 2014, this critical juncture was not signed. Consult the Trail Run Project mobile app here to make sure you make the turn.

Let the pain begin as you ascend southwestward to Trail Rider Pass over the stunning Snowmass Lake and under the eastern flanks of the hulking Snowmass Mountain (14,092').

From Trail Rider summit (12,500'), enjoy sweeping views of the remote West Elks & brace your skeleton for the steepest, most jarring descent of the day.

Note: If you encounter dangerous weather, a possible bailout is to exit to the southwest at the Geneva Lake trailhead, where you can probably hitch a ride with a 4x4 on the Lead King Loop down to Marble to make a pickup call.

About two miles off the top of Trail Rider, keep a sharp eye out for your next critical left turn, onto the unsigned North Fork Cutoff Trail. For the next mile you'll traverse southeast on a steep hillside until merging with North Fork Crystal River. If you need a break, this is a good spot to fill up water and get off your feet. After another mile, look for a ridiculous waterfall & enter the pain cave once again as you switchback above the falls to enter the otherworldly Fravert Basin.

From here, it's 2.75 miles under Maroon Peak (14,156') through unreal alpine terrain to the top of Frigid Air Pass. Keep some gas in the tank to savor this section. From Frigid Air summit (12,500'), take heart because you have just two miles and much less vertical relief to Maroon Pass.

Halfway between the passes, go straight toward Maroon at a T, meeting West Maroon Trail. Punch it over your final 12,500' pass, and cruise the last seven miles down the West Maroon Creek drainage to your cooler.

Flora & Fauna

More wildflowers than you can count...


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Your Check-Ins


Aug 25, 2018
Derrill Rodgers
Super beautiful route. 27mi — 10h 20m
Aug 16, 2018
Elliott Bates
So rad. The last 5 miles not rad, so many rocks
Aug 12, 2018
Benjamin Tolomeo
Aug 9, 2018
Marissa DeMercurio
Aug 3, 2018
Aug 2, 2018
Mr Singleton
First attempt. Blown away. Can’t wait to go back 27mi
Jul 28, 2018
rick s
Worth it
Jul 27, 2018
Lynn Froetscher

Trail Ratings

  5.0 from 96 votes


  5.0 from 96 votes
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There's some serious warning about lighting risk after 11AM, any recommendations on how to cope with that? when would be a good start time? Aug 7, 2017
Great late-August run. Plenty of water, great weather. Truly world class! Sep 4, 2017
Lauren Atkinson
Gunnison, CO
Lauren Atkinson   Gunnison, CO
I was on the route last week and noticed toilet paper EVERYWHERE and even a few piles of un-buried human waste. I'm curious how runner handle their poop and toilet paper when running this loop? Jul 31, 2018

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