Four Pass Loop Gear Checklist
The Four Pass Loop is a 26-mile circuit near Aspen that crosses four passes above 12,000 feet, and nearly everything hikers pack for it comes from the altitude. The Forest Service requires a hard-sided bear canister and an advance permit for the Snowmass Lake and Geneva Lake zones. On top of that, the hikers we read carried sleep systems built for mid-20s nights, full rain gear for afternoon storms, trekking poles, and a way to treat stream water, because there is none to drink at the trailhead.
What shapes your gear on Four Pass Loop
- Length and passes
- The Forest Service calls it a 26-mile circuit over four passes higher than 12,000 feet. Other guides measure it at 28 miles. Most parties take four days, and one report says only very fit hikers should try it in fewer.
From White River National Forest (USDA Forest Service), Field Mag and Backpackers Review
- Trailhead and water
- The loop starts near 9,500 feet. The Maroon Lake trailhead has vault toilets and trash cans but no drinkable water, and the Forest Service lists no potable water at the site.
From Backpackers Review and White River National Forest (USDA Forest Service)
- Season and weather
- The Forest Service names July through September as the best window, and says campsites, trails and passes are snow covered from early October to late June. Afternoon thunderstorms are common, so crossing passes in the morning is the usual plan.
From White River National Forest (USDA Forest Service) and Backpackers Review
- Permit zones
- Advance reservations on Recreation.gov are required for overnight stays in the permit zones that include the Four Pass Loop, Snowmass Lake and Geneva Lake. You reserve a spot in each zone where you plan to camp. Outside those zones you self-register at the trailhead.
- Cell service
- One runner who did the loop in a day had no signal at all, and put the phone in airplane mode because the battery was draining.
From Team runrun
What the agency requires on Four Pass Loop
An approved bear-resistant container
Everything with a smell, meaning food, garbage and toiletries, goes in a bear-resistant container on the IGBC approved list. Anyone found without one is ticketed and sent out, the Forest Service says.
A plan for human waste
Free WAG bags are handed out at the Conundrum Creek and Snowmass Lake trailheads and must be packed out. Without one, solid waste is buried in a cathole 6 to 8 inches deep, 200 feet or more from water, camp and trails.
Overnight permit for each reserved zone
The permit holder reserves a campsite spot in every permit zone where the group camps. Groups are limited to 10 people, and dogs are not allowed.
What hikers carry on Four Pass Loop
A sleep system that reaches the mid 20s
Forum users told a planner with a quilt and insulated hoody that the loop sleeps high and that forecasts hide cold clear nights. One recalled waking on August 1 to an inch of ice on the tent. Another, who went the year before, slept warm in a summer-weight down bag without using insulated clothing.
Rain jacket, rain pants and rain mitts
A hiker with a rest day at Snowmass Lake was glad of rain mitts and pants because rain fell all day. Guides tell hikers not to forget rain gear because most people get stormed on at least once, and a runner calls the passes dicey in poor weather.
From Backpacking Light forum, Field Mag and Team runrun
A windshirt for dew-soaked brush and exposed ridges
One hiker found a windshell useful when walking wet brush in the mornings. Another called a windshirt the most versatile piece of gear in the mountain West, good for light rain, bugs and warmth around camp.
Wool or synthetic clothes for camp and no cotton
A trip report recommends warm wool for the cold mornings and evenings at higher campsites, and hiking clothes that dry after a storm. Cotton that gets wet keeps you cold.
From Backpackers Review
A bandana or wide-brim hat, soaked in a stream
There is a lot of time above treeline with no shade. A trail guide suggests wetting a bandana in a stream and wearing it.
From Field Mag
Trekking poles
The passes mean steep climbs and descents, and two writers list poles as something not to forget.
From Field Mag and Backpackers Review
A filter or chemical treatment
The route passes a handful of streams and lakes, and the runner says to drink from them at your own risk without purification. A runner emptied a 1.5 liter bladder after the third pass, refilled from a trickle and wished for purification. The trip report says to filter all water.
From Team runrun and Backpackers Review
A headlamp and a paper map
The loop is well marked, but signs mark the individual passes but not the loop as a whole, and there is no cell signal. A forum gear list for the loop carries a compass and a wilderness map.
From Team runrun, Backpacking Light forum and Backpackers Review
10 people can go on one permit. Split this list between them so nobody carries two stoves.
Plan a trip hereWhat hikers regret or leave behind on Four Pass Loop
A 40-degree sleep system
Several forum users told a planner that a lightweight quilt with a hoody and pants was good to about 40 degrees, but the loop can drop to the mid 20s, so they advised the warmer bag as insurance.
Skipping water treatment
A runner took a chance on an untreated stream trickle and wished for a purifier. It worked out, but it is the item this runner named first.
From Team runrun
Underestimating how long the loop takes
The same runner took longer than expected even while moving fast, and says to pack enough fuel, rain gear, a hat and gloves for hot, cold, wet and dry in one day.
From Team runrun
Gear questions for Four Pass Loop
Do you need a bear canister for the Four Pass Loop?
Yes. The Forest Service requires every backpacker in the wilderness to carry a bear-resistant container from the IGBC approved list, and tickets visitors who do not have one.
Do you need a permit for the Four Pass Loop?
For overnight stays in the permit zones that include the loop, Snowmass Lake and Geneva Lake, yes, through Recreation.gov in advance. Older trip reports describe trailhead self-registration with no quota, which is no longer true for those zones.
From White River National Forest (USDA Forest Service) and Backpackers Review
How cold does the Four Pass Loop get at night?
Cold enough to plan for the mid 20s. A forum member woke to an inch of ice on the tent one August 1, and others say forecasts can understate clear-night lows at altitude.
Is there drinking water on the Four Pass Loop?
Not at the trailhead. Streams and lakes are plentiful along the route but hikers filter or treat all of it.
From White River National Forest (USDA Forest Service), Backpackers Review and Team runrun
Sources
- Maroon Bells-Snowmass Wilderness · White River National Forest (USDA Forest Service) · Agency
- A Guide to Backpacking Colorado's Legendary Four Pass Loop · Field Mag, Alex Eaton · Blog
- Four Pass Loop - Maroon Bells Snowmass Wilderness, CO (28 mile loop) · Backpackers Review · Trip report
- Four Pass Loop Maroon Bells Trip Report · Team runrun, Jeff U · Trip report
- Four Pass Loop gear thread · Backpacking Light forum · Forum thread