Four Pass Loop

The Four Pass Loop is the best-known backpacking trip in Colorado: 28 miles around the Maroon Bells over four passes above 12,000 feet, through wildflower basins, past Snowmass Lake, and back to Maroon Lake, usually in three or four days. The scenery is why the overnight permits sell out within minutes of release each year. It is on this site as a trail because people plan for it a year ahead.

From Maroon Lake, the loop runs either direction; counterclockwise puts the steep climb to Buckskin Pass first and most guidebooks describe it that way. The Maroon-Snowmass trail climbs past Crater Lake and up Minnehaha Gulch to Buckskin Pass at 12,462 feet, then drops to Snowmass Lake, the usual first camp, about 9 miles in. Day two climbs Trail Rider Pass at 12,420 feet and descends into the Fravert Basin, with the North Fork of the Crystal River and a big waterfall.

Day three climbs Frigid Air Pass at 12,400 feet, crosses the head of the Fravert Basin into the meadows below the Bells' back side, and continues over West Maroon Pass at 12,500 feet, the loop's high point, before dropping the West Maroon valley past Crater Lake to Maroon Lake. Strong parties do it in two days; three is the sensible plan, and four leaves time for the side trips.

Everything starts at Maroon Lake. Overnight permits for the Maroon Bells-Snowmass Wilderness are required from May through October for every camp on the loop and are reserved on Recreation.gov, with the season's permits released in advance and gone within minutes for July, August, and September dates. The Maroon Creek Road reservation applies too: a shuttle seat from Aspen Highlands or a pre-8 AM parking permit, and overnight parking at the lake needs its own arrangement through the same system. Bear canisters are required.

Dogs are allowed on leash throughout, though the length, the talus, and the goats argue against bringing one. Not a kid trip. Each pass day carries 2,500 to 3,000 feet of climbing at altitude, and the trailhead is at 9,580 feet; acclimatize in Aspen first. Camp only at the designated sites in the zone your permit names, 100 feet from water, no fires. Snowmass Lake and Crater Lake are the busiest camps. Water is everywhere and needs a filter. Aspen has the gear shops and the last meal. The Maroon Bells visitor guide covers the reservation system, and the Colorado backpacking checklist covers the pack.