Four Pass Loop - West Maroon to Buckskin


Bear canisters are required for all backpackers in the Maroon Bells-Snowmass Wilderness.
• Advance reservation permits are required for overnight stays in the Maroon Bells - Snowmass Wilderness Overnight Permit Zones.

Get Permits

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 12,000 ft, past clear alpine lakes and among the rugged Elk Range peaks.

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. 

The Four Pass Loop is considered a difficult and challenging route due to the elevation and terrain.


At a Glance

Current Conditions: The Four Pass Loop is often snow-bound from October through June.
Reservations: Summer travel on Maroon Creek Road is restricted. Reservations are required to access the Maroon Bells Scenic Area by vehicle or Roaring Fork Transit Authority( RFTA) shuttle. Some Maroon Bells - Snowmass Wilderness trailheads are within the Maroon Bells Scenic Area. See Maroon Bells Scenic Area for specific access and logistics.
Fees: Fees are charged for high season overnight stays in permitted zones of the Maroon Bells - Snowmass Wilderness, and for parking and shuttle reservations at Maroon Bells Scenic Area.
Permit Info: A permit is required for overnight stays in Maroon Bells-Snowmass Wilderness Overnight Permit Zones. This permit must be acquired in advance at 
For all other overnight trips to the Maroon Bells-Snowmass Wilderness, registration is required at the trailhead.  
Usage: Heavy
Best Season: July - September

Maroon Bells - Snowmass Wilderness regulations protect this special place:

  • Overnight permit required for overnight stays within the Maroon Bells-Snowmass Wilderness Overnight Permit Zones.
  • Food, trash and any scented items must be stored in an IGBC approved bear resistant containerHuman food habituated bears are a threat to human safety. Visitors without approved bear resistant containers will be ticketed and required to leave. 
  • You must have a plan for human waste. Human waste bags (WAG) bags are highly recommended and are available free of charge at the Conundrum Creek and Snowmass Lake trailheads. WAG bags must be packed out. Learn more about how to use a WAG bag. If a WAG bag is not used, visitors are required to deposit solid human waste in holes dug 6 to 8 inches deep at least 200 feet (70 paces) from water, camp and trails.
  • Group size is limited to 10 with no more than 15 stock animals in one group. Large groups multiply impacts to the wilderness and disrupt the solitude of others.
  • Dogs are prohibited in the Conundrum Creek Valley from Silver Dollar Pond to Triangle Pass, including the hot springs.  Everywhere else, dogs must be leashed.
  • Campfires are prohibited at all designated sites at Conundrum Hot Springs, Capitol Lake, Crater Lake and above 10,800 feet including Snowmass Lake. Campfires consume wood, accumulate trash, kill fragile alpine vegetation, sterilize the soil and scar the land. Lightweight camp stoves are recommended.
  • Campers must camp in designated sites at Conundrum Hot Springs, Copper Lake, Crater Lake, Geneva Lake, Capitol Lake and Thomas Lakes.  Everywhere else campers should set up more than 100 feet from lakes, streams and trails and use previously impacted campsites.  Camp out of sight of others and away from fragile areas.
  • As with all designated Wilderness, motorized and mechanized equipment is prohibited including bicycles, motorbikes, chainsaws, ATVs, carts, drones, hang gliders and paragliders. This equipment is prohibited to provide visitors with a primitive recreational experience and to preserve outstanding opportunities for solitude.
Closest Towns: Aspen, Colorado
Water: Treat and filter all water
Restroom: No restrooms in Wilderness; see Restrictions
Information Center: Aspen-Sopris Ranger Station: 
620 Main Street
Carbondale, CO 81623

Recreation Map

Map showing recreational areas. Map Information


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 the party's 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'