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

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12,454' 3,796 m


9,576' 2,919 m


7,265' 2,214 m


7,266' 2,215 m



Avg Grade (6°)


Max Grade (28°)

Dogs Leashed

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

Advance reservation overnight permits are required for the busiest areas of the Maroon Bells-Snowmass Wilderness including Conundrum Hot Springs, Capitol Lake, Crater Lake, and the Four Pass Loop (including Snowmass Lake and Geneva Lake). Permits must be purchased in advance at

For more information, check out the US Forest Service's website.


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

Need to Know

Camping permits are required in the Maroon Bells-Snowmass Wilderness. Additionally, parking permits are required at Maroon Lake, which can sell out months in advance. It is recommended that you park in Aspen and take the public bus from Highlands Ski Area to access Maroon Lake. Bus reservations are also required, but are much easier to acquire. When traveling back to Aspen from Maroon Lake, bus reservations are technically required but there is more leeway with which bus you take down, especially during non-peak times and at the very end of the day.

Approved bear food storage containers are also required and strictly enforced.


Begin at the Maroon Snowmass Trail. This route is described counter-clockwise, going Buckskin Pass, Trail Rider Pass, Frigid Air Pass, West Maroon Pass. Either way is great, though it is more commonly travelled counter-clockwise.

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). Climb up and through treeline with incredible views of the north face of North Maroon Peak rising above you. At the intersection for Willow Pass and Buckskin Pass, stay left to climb the final headwall up Buckskin.

From the top of Buckskin Pass, turn around to savor the early morning sun on Pyramid Peak (14,018'), then turn and find the trail down and to your right that descends into the densely forested Snowmass Creek drainage. After about 2.5 miles from the top of Buckskin, take a left over a creek crossing (there are usually sturdy logs stacked across this crossing, but high focus and good balance are a must!). Continuing straight puts you on a meandering trail that leads to campsites further down the valley. After crossing the creek, start a short climb towards Snowmass Lake, and eventually arrive at a T-intersection with Geneva Lake Trail heading to your left (this is an easy one to miss, so make sure to consult the mobile app to stay on track).

Follow the Geneva Lake Trail until you arrive close to the southeast shore of Snowmass Lake. If it's a hot day venture down to the water for a quick swim or continue on your way by taking another left toward Trail Rider Pass. Let the challenge begin as you start climbing steeply southwestward to Trail Rider Pass, high above 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 Elk Mountains & brace your legs for the long descent into the North Fork of the Crystal River valley.

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 (you'll find this intersection a few minutes after starting a descent next to a steep creek). After making the left turn, you'll traverse and descend southeast on a steep hillside for a little over a mile until merging with the North Fork Crystal River trail. Head upstream, eventually coming to a wide and unavoidable frigid river crossing (low current) that will put a knot in your stomach as you cross it no matter what time of year! If you need a break, this is a good spot to fill up water and get off your feet. Another mile on, look for a spectacular cascading waterfall & start climbing steeply again as you switchback above the falls to enter the otherworldly Fravert Basin.

From here, it's 2.75 miles under the broad southwest face of Maroon Peak (14,156') through unreal alpine terrain to the top of Frigid Air Pass. From the top of the pass (12,500') descend steeply to a bench where you'll turn east and traverse toward West Maroon Pass. Savor the fact that you don't lose nearly as much elevation between these two passes as you did the previous ones!

A little over 1.5 miles from the top of Frigid Air Pass you'll come to a T-intersection. Take a left toward West Maroon Pass and start the last major climb toward you're fourth and final pass. After cresting the pass, descend through seemingly endless willow groves until you eventually meet the south shore of Crater Lake. Work your way along the west side of the lake, sticking to the most trodden path as there are numerous bandit trails and campsite spurs that can you lead you astray. Pass the Buckskin Pass turnoff, keeping right, and head down the homestretch and back to your car/public bus.

Flora & Fauna

More wildflowers than you can count...


Shared By:

Jason Smith with improvements by Spirit 45 CluB

Trail Ratings

  4.9 from 216 votes


  4.9 from 216 votes
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271 Views Last Month
187,433 Since Feb 9, 2015
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One hell of an evening at the Maroon Bells
Sep 27, 2015 near Snowmas…, CO
Feb 9, 2015 near Snowmas…, CO
Running up heavenly Fravert Basin. Photo: Michelle Smith
Aug 31, 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
Camping off buckskin and enjoying the view.
Nov 9, 2019 near Snowmas…, CO


Current Trail Conditions

Add Your Check-In


Aug 1, 2023
M Abe
Sep 16, 2022
Gabriel Poulin
27.3mi — 10h 15m
Dec 8, 2021
Irina Garbuz
Aug 26, 2021
Kristina Chang
Sprained ankle 14 miles in heheh 28.5mi — 11h 09m
Jul 31, 2021
Michelle Kent
Beautiful loop! Well maintained trail. gpx file did the job for navigation. 28mi — 8h 23m
Sep 27, 2020
Blake Batchelor
Great route! Went clockwise
Aug 22, 2020
Corbin Larsen
28.6mi — 10h 00m
Aug 8, 2020
Nate Roedl

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