The Four Pass Loop is one of Colorado’s most well known hikes. The Maroon Bells are the backdrop to many photos depicting the Aspen area. This Four Pass Loop will take you through these high peaks and into some of the most otherworldly looking alpine basins for an unforgettable backpacking trip.
How to get there: From Aspen
From Aspen, you will drive .5-mile West on Highway 82. You’ll come to a roundabout where you will go right onto Maroon Creek Drive. Drive 9.5 miles until you come to the overnight parking lot at Maroon Lake. If this lot is full, you can try the West Maroon Portal lot.
The trailhead can be found at Maroon Lake. To avoid having to take a shuttle, you must enter the Maroon Bells Scenic Area before 8AM or after 5PM. Otherwise, you will not be able to access the trailhead with your vehicle. There is a $10 entrance fee that you will need to pay.
The trailhead for the Four Pass Loop will be the Maroon Snowmass Trailhead. Parking at the trailhead can be packed during Summer, so come as early as you can to get your spot.
The shuttle can take you within 5 minutes from Maroon Lake and the trailhead, so if you do have to park outside and hitch a ride, it will not be the end of the world.
Trailhead location: goo.gl/maps/
What To Expect on The Trail
Length – In just over 27 miles, you will gain 7,327 feet of elevation. At its highest point, you will be well above timberline at 12,454 feet above sea level. Never going below 9,000 feet above sea level, it is vital to come prepared with enough food and water/water filtration system to restore energy.
Acclimatization – If you are not a Colorado resident, or not used to being at such high elevation, take a while to acclimate yourself before attempting this trail. The Four Pass Loop is quite committing, and not an area you will want to deal with altitude sickness or bail early.
As you probably guessed, the trail takes you over four passes: West Maroon Pass, Frigid Air Pass, Trail Rider Pass, and Buckskin Pass.
Number of nights – This Four Pass trail is typically done in four days. The trailhead information describes the loop going counterclockwise: starting with Buckskin Pass, Trail Rider Pass, Frigid Air Pass, and West Maroon Pass. Either way will leave you with the same views and the same steep ascents and descents.
Difficulty – The trail becomes steep in sections as you move over the passes. Be cautious while ascending and descending these sections as loose rock can be hazardous here. These bits of the trail are very technical, but overall the trail is deemed “Intermediate.”
Taking The Trail Counterclockwise:
- The trail begins with a 1.5-mile gradual incline as you approach the peaks that make this trail so popular. If you take a right at the T-intersection and head toward Buckskin Pass, you will soon see North Maroon Peak, standing tall at 14,014 feet above sea level. Take in the gorgeous views as you begin your first sharp incline into Buckskin Pass.
- As you descend Buckskin Pass, you will find yourself back in the dense forest that surrounds Snowmass Creek. There will be another T-intersection, go left for the Geneva Lake Trail. This intersection is not well marked, so remember just to stay left at the first T, or bring a map and compass.
- From here, you will quickly ascend Trail Rider Pass. Beat the pain while looking over the beautiful Snowmass Lake and the looming Snowmass Mountain.
- Descending Trail Rider Summit will be the harshest descent of the trail. About 2 miles from the summit of Trail Rider, you will take another left turn onto North Fork Cutoff. This is unmarked as well, so pay close attention!
- From here, you will traverse a steep hillside until coming to the North Fork Crystal River. This is a popular break spot after the harsh descent, and one of the first spots to filter water.
- You will soon come across a surreal waterfall and find yourself on switchbacks… The switchback ascent is well worth it once you take your first glance of Fravert Basin. Fravert Basin will leave you speechless with its views and abundant wildflowers.
- Savor this gorgeous terrain for 2.75 miles until you reach the top of Frigid Air Pass. After Frigid Air, you will come to Maroon Pass. There is only a 2-mile grueling stretch in between these rough sections, so take your time and save your energy!
- You will take your final turn onto West Maroon Trail. This will be your final push up to 12, 454 feet above sea level!
- From this last summit, enjoy the descent down West Maroon Creek drainage for a solid 7 miles until you reach your vehicle (and sweet relief).
Bear Canisters Required
Bears are prominent in the area! While camping, it is important to follow Leave No Trace Principles. LNT principles will help you avoid any unwanted bear encounters and will help keep this environment wild.
Because of the abundant bear activity here, Bear Bags have been shown to not work well in this area. Bear Canisters are required by law throughout the Maroon Bells-Snowmass Wilderness Area for any overnight stay. One of these will help protect you, your campsite, and your food. You can rent bear canisters from REI! There are also places in Aspen that offer bear canister rentals for the area for decent prices.
Dogs are allowed here as long as they are on leash at all times. While they are allowed, I personally wouldn’t want to put my dog at risk of a bear run in.
Parking and Camping Permits
The Maroon Bells-Snowmass Wilderness Area is public land in a National Forest, so no permit is required outside of the $10 vehicle overnight permit purchased as you drive the road to the trailhead parking lot.
Dispersed camping is permitted in the Maroon Bells-Snowmass Wilderness Area, which means no camping specific permits required as well.
Campsites Along The Loop
Campsites are easy to find, and you will come across many that have become semi-established just by use over the years. It is best to camp in one of these sites if you can to avoid creating more areas like this.
This trail can be done in as little as 1.5 days and as much as 5 days if you really wanted to split it up. If you have the time, I highly recommend splitting the days up. Due to the dramatic elevation gains and losses, your legs will definitely be feeling it by the end of the day.
If your body is not used to being at high elevation, splitting the trail up is necessary. Your body will need extra time to restore energy and hydrate.
When camping, find a spot that is 200 feet away from any water source, and 200 feet away from the trail. You will find the semi-established campsites by various smaller, social-trails that have been made.
Trail Conditions and Best Time Of Year To Visit
The best trail condition information will be found on websites such as Hiking Project, or AllTrails. I’ve noticed the stats on the AllTrails page for this trail are a little off as far as mileage, but AllTrails is still a popular site for people who have recently hiked the loop to review it and provide useful information to others.
For both sites, the hiker reviews can be found toward the bottom of the trail listing. These reviews will be your best way of getting information about seasonal changes such as snowpack or any washouts that might’ve happened to affect the trail.
These websites do have weather posted on the trail information page, but it is not terribly accurate. To get the best weather information on the area, check sites such as Weather Underground or use a radar app. Some radar apps work off of GPS signal, which will help a lot while on the trail as well. Some higher-end GPS communicators/navigators can also provide weather information and updates while on the trail.
- The best season to hike this trial is between April and October. This varies every year due to snow and early winter storms, so July/September is the most popular time to hike this trail due to the warm weather.
- April-May is a great time to avoid other hikers as the nights will be cooler and snow may still be on the ground. To hike during this time, it will be in your best interest to bring some sort of shoe traction slip-ons like the Kahtoola Microspikes to avoid sliding on snow during the steep sections on this trail.
- September/early October will be cooler at night, but the mosquitoes will all be gone! This will also be a great time to avoid other hikers who won’t want to deal with colder nights. Due to the cold and impending winter, bears will also be in feasting mode preparing for hibernation. This is when you need to be extra diligent about storing food and should definitely leave the pups at home.
At altitude, storms can happen quickly and without any warning. No matter the season, come prepared with rain gear such as a waterproof jacket and rain-pants that you can put on over your layers. If your pack is not waterproof, a pack cover will help keep everything else dry.
Related article: Hiking In The Rain | 27 Tips From An Outdoor Adventure Guide
Even in the middle of summer, nights will be cool here so bring a warm sleeping bag and insulating layers. My favorite trick to stay warm in my tent is to snag one of the hot rocks used in our fire-pit, wrap it in a dirty shirt, and put it in the bottom of my sleeping bag (just make sure it’s not too hot to burn through anything).
Trail Map and GPS Navigation Devices
If you have a way to charge your phone while hiking, you can download maps from your favorite trail app to use. This can be an easy way to track your progress and stay on route, but relying on your phone to stay alive can be iffy.
Other popular options are GPS navigators such as the Garmin InReach Explorer+ or InReach Mini. These are helpful tools in the backcountry as they are satellite communicators that have navigation capabilities to use while route-finding.
A GPS communicator is highly recommended in this wilderness area of Colorado due to the seclusion of this trail, bear activity, and steep sections that can easily cause accidents. There is no need to sacrifice safety when you lose cell-service in the backcountry.
The old school option is to bring a physical map and compass with you! A map and compass are great alternatives because they do not rely on any service. Even satellite service can take a little bit to come through.
The key to using a map and compass is knowing how to use them, though. Might sound like a silly thing to say, but many people have never been taught how to properly use a map and compass and end up in trouble when they get off-trail.
Snowpack and washouts can affect this trail quickly, so it is important to come prepared with some sort of map.
Caltopo Trailmap With Suggested Overnight Locations (3 Days)
Four Pass Loop from Crested Butte
The Four Pass Loop can also be reached from Crested Butte, Colorado. South of Aspen, Crested Butte offers just as much (if not more) recreation possibilities. Listed in our “10 of Colorado’s Best Less-Traveled Mountain Towns”, Crested Butte is a ski town that has held onto its small-town roots.
Take Gothic Road/Route 135 North for 14 miles over Schofield Pass. Shortly after the pass, you will find the parking lot and trailhead for Maroon Snowmass Trailhead.
Trailhead location: goo.gl/maps/
Where to get a bite after
I don’t know about you, but all I want after a long hike is a burger, fries, and Coca-Cola – usually followed by a beer. No matter how much my body just wants to crawl into bed, my brain wants food and a hot second to decompress.
If you are returning to Aspen after your trek, and in need of a hearty dinner, check out the 520 Grill. One of the cheaper eateries in Aspen, the 520 Grill serves great burgers and other quick bites.
If you just want food to-go to bring with you straight to the couch (usually the only place I want to go after 4 days in the backcountry), 520 Grill offers carry-out!
If you are coming from Crested Butte, The Last Steep Bar & Grill is one of the best places to enjoy a burger and beverage in this cozy mountain town.
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Daniell is a certified outdoor climbing guide with professional experience climbing throughout Colorado’s Western Slope region. She is based out of Fort Collins, CO and enjoys trail running, desert climbing and overnight canoe trips.