Trail Run Project Logo

Four Pass Loop


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

Your Rating:      Clear Rating
Your Difficulty:
Your Favorites: Add to Favorites · Your List
Zoom in to see details
Map Key







12,454' 3,796 m


9,571' 2,917 m


7,327' 2,233 m


7,329' 2,234 m



Avg Grade (6°)


Max Grade (28°)

Dogs Leashed

Features Birding · Commonly Backpacked · 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.

Bear canisters are currently required in the Maroon Bells-Snowmass Wilderness. More information on current regulations can be found here.


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...


Shared By:

Jason Smith with improvements by Spirit 45 CluB

Trail Ratings

  5.0 from 179 votes


  5.0 from 179 votes
5 Star
4 Star
3 Star
2 Star
1 Star
Recommended Route Rankings


in Colorado


1,022 Views Last Month
165,540 Since Feb 9, 2015



One hell of an evening at the Maroon Bells
Sep 27, 2015 near Snowmas…, CO
Running up heavenly Fravert Basin. Photo: Michelle Smith
Aug 31, 2015 near Snowmas…, CO
Feb 9, 2015 near Snowmas…, CO
Maroon Bells
Apr 1, 2015 near Snowmas…, CO
One of the many amazing high country lake views found on the Four Pass Loop.
Feb 1, 2018 near Snowmas…, CO
Maroon Bells on a beautiful fall day
Feb 8, 2018 near Snowmas…, CO


Current Trail Conditions

Update Conditions
Unknown See History
Add Your Check-In


Sep 27, 2020
Blake Batchelor
Great route! Went clockwise
Aug 22, 2020
Corbin Larsen
28.6mi — 10h 00m
Aug 8, 2020
Nate Roedl
Aug 7, 2020
Kristin Louderback
Amazing wildflowers. Plenty of running water. Friendly faces. Physically and logistically challenging but worth the effort! 27mi — 8h 38m
Aug 1, 2020
Jacob Torrey
27.3mi — 10h 30m
Jul 7, 2020
Guido Sarducci
27.2mi — 9h 00m
Sep 20, 2019
Josiah Tharp
Lots of hype on this trail. I can confirm that it does, in fact, live up to the hype. Views did not suck. 27.5mi
Sep 14, 2019
Nick Leuck