ALERT: Due to recent bear activity, bear canisters are required for all backpackers in the Maroon Bells-Snowmass Wilderness.
The famous Four Pass Loop backpacking route in the Maroon Bells – Snowmass Wilderness is an international treasure. This 26 mile (42 km) circuit climbs over four mountain passes higher than 12,000ft, past crystal clear alpine lakes and among the rugged beauty of the high Elk Range peaks. Thousands of people every summer make the journey to see these sights. With proper planning and a little common sense consideration, everyone can enjoy the Wilderness experience they are seeking while protecting this fragile alpine world for future generations.
The Maroon Bells – Snowmass Wilderness is a place of untrammeled natural beauty where each visitor must be self-reliant to face the risks and challenges of mountain travel. 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. Overcoming these challenges offers visitors’ the Wilderness reward of self-discovery and overwhelming beauty.
The official information on this site is the most current and accurate information supplied for planning a backpacking trip on the Four Pass Loop. Please observe all recommendations and regulations to help the US Forest Service protect this unique experience and wild landscape for all.
The Four Pass Loop is often snow-bound from October through June. Call the Aspen Ranger Station (970.925.3445) or check this link for current NOAA Weahter conditions. Many people access the Loop from the Maroon-Snowmass trailhead at Maroon Lake. This access point is subject to the restrictions of the Maroon Bells Scenic Area, a recreation fee area. For further information, click on the Maroon Bells Scenic Area link or call the Aspen Ranger Station.
No fee is required to be in the Maroon Bells – Snowmass Wilderness or hike the Four Pass Loop. To access the trailhead at Maroon Lake, you must enter the Maroon Bells Scenic Area before 8am or after 5pm before the shuttle busses begin for the day, which a $10 entrance fee is required. For further information, click here to link to the Maroon Bells Scenic Area webpage or call the Aspen Ranger Station.
All overnight visitors to the Maroon Bells – Snowmass Wilderness must self-register at the trailhead kiosks. Each overnight party in the Wilderness is required to possess a copy of the registration tag at all times. The purpose of this required registration is to educate visitors about Wilderness ethics and to gather visitor use information that is used to inform the management of the area.
The US Forest Service and you are responsible for the stewardship of this wild place so that all can enjoy a Wilderness experience and this landscape will retain its’ wild character in perpetuity. The extremely high use on the Four Pass Loop results in cumulative negative impacts to the natural resources and visitor experience in the area. Please practice Wilderness and Leave No Trace ethics to minimize your impact on the Wilderness by observing the following regulations posted at wilderness.net
Treat & filter all Wilderness water sources. Protect water quality with proper waste disposal.
Consider packing out human waste. Dispose & bury human waste 100+ feet from water, trails, & camps.
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.
Camping & Cabins
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).
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.
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.
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.