Four Pass Loop - West Maroon to Buckskin

Views of wildlife on the Four Pass Loop trail

ALERT: Bear canisters are required for all backpackers in the Maroon Bells-Snowmass Wilderness. 

The famous Four Pass Loop backpacking route within Maroon Bells – Snowmass Wilderness is an international treasure. This 26 mile (42 km) circuit climbs over four mountain passes higher than 12,000ft, past clear alpine lakes and among the rugged Elk Range peaks. Thousands of people every summer make the journey to see these sights. 

Make sure to plan ahead and know before you go! Early summer snowmelt makes the river crossing perilous and deep snow persists on the passes until late in the summer. Sudden thunderstorms can catch travelers exposed far from the cover of tree-line in mid-summer and snow fall returns to the high country early. 

Please observe all recommendations and regulations to help the US Forest Service protect this unique experience and wild landscape for all.

View a downloadable trail guide: Four Pass Loop Trail Guide (PDF)

View select campsite location & restrictions (PDF) 

At a Glance

Current Conditions: Call Aspen Ranger Station (970) 925 3445 or check current NOAA Weather conditions. Note: The Four Pass Loop is often snow-bound from October through June.
Fees: No fee is required to backpack in the Maroon Bells – Snowmass Wilderness or hike the Four Pass Loop. Many people access the Loop from the Maroon Lake trailhead at Maroon Lake within Maroon Bells Scenic Area, a recreation fee area.  
Permit Info: All overnight visitors to the Maroon Bells – Snowmass Wilderness must self-register at the trailhead kiosks.  Each party is required to possess a copy of the registration tag at all times. The purpose of required registration is to educate visitors about wilderness ethics and gather visitor use information so we can better manage the area.
Usage: Heavy
Closest Towns: Aspen, Colorado
Water: Treat & filter all water sources. Protect water quality with proper waste disposal.
Restroom: Consider packing out human waste. Dispose & bury human waste 100+ feet from water, trails, & camps.
Information Center: Aspen Ranger District

General Information


The Maroon Lake trailhead is located 6 1/2 miles southwest of Aspen, Colorado, on Maroon Creek Road. From Highway 82 take the Maroon Creek Road exit at the roundabout on the West edge of town. Follow Maroon Creek Road to the Maroon Bells Welcome Station.  Day users and overflow backpackers be asked to park at Aspen Highlands and take a bus to the trailhead. Backpackers parking at the Maroon Lake trailhead, please only park in the designated overnight lot.

From mid-June through September, day use traffic is restricted on Maroon Creek Road between 8:00 a.m.—5:00 p.m. See Maroon Bells Scenic Area for more information about access to the Scenic Area.

General Notes:

Please use Leave No Trace ethics. Review the video Wilderness in Peril:

Recreation Map

Map showing recreational areas. Map Information


Campground Camping

No facilities (cabins, campgrounds, toilets…) are provided along the Four Pass Loop trail, or any other trail located in the Maroon Bells-Snowmass Wilderness Area.

Visitors wishing to camp at either Crater Lake or Geneva Lake must camp in designated sites.

In all other areas, visitors should find an impacted campsite that is 100+ feet from trails and water sources.  Ideal camp sites are not visible from the trail and so are easier to find in the day light.  Be aware of and respect areas that are closed to camping and camp fires (closed tree-line and above).   

RV Camping

River and Stream Fishing

Fishing is permitted in all streams and lakes within the Maroon Bells – Snowmass Wilderness subject to the regulations of Colorado Parks and Wildlife.


The Four Pass Loop accessed from the Maroon Lake trailhead is 26 miles with ~11,000 ft. (3,350 meters) of vertical gain.  Depending on a parties’ ability, trail and weather conditions, this loop can take between 3 and 5 days to complete.  Many enjoyable side hikes, detours or alternate access points can be added to make the Loop longer.

Example Itinerary

Day 1    Maroon-Snowmass TH at Maroon Lake – Hike to Crater Lake and turn south along the West Maroon Trail.  Cross the creek and hike a little further to find nice secluded campsites off both sides of the trail. 

Day 2    Cross the creek early before climbing to the top of W. Maroon Pass (12,500 ft.).  Drop down into the expansive alpine basin of the East Fork staying right at the signed junction, before climbing again to the top of Frigid Air Pass (12,400 ft.).  From here, drop down into the forest of Fravert Basin to find a camp above or south of the trail before King’s waterfall. 

Day 3    Continue west along the North Fork of the Crystal before crossing it at a wide point.  Shortly after this crossing take a right up the cutoff trail towards Trail Rider Pass (12,420 ft.).  From here it is a steep descent to Snowmass Lake where you make camp 100 ft. from the lake, stream and trails. 

Day 4    From Snowmass Lake take the Maroon – Snowmass Trail towards Buckskin Pass (12,500 ft.).  Descend to Crater and then Maroon Lake to finish your loop.

Permit required?: Y
Difficulty Level: More Difficult


The short (1.75 mi – one way) hike to Crater Lake offers a preview of the Four Pass Loop and a great spot for a day hike.

Recreation Areas

Recreation Activities


  Area/Length : 
28 miles round-trip

  Latitude : 

  Longitude : 

  Elevation : 
9,580' - 12,500'