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A demanding North American Classic in the heart of the Cascade Mountains.

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7,828' 2,386 m


1,530' 466 m


10,892' 3,320 m


13,022' 3,969 m



Avg Grade (8°)


Max Grade (47°)

Dogs No Dogs

Features Fall Colors · Views · Waterfall · Wildlife

This route starts in North Cascades National Park; but then straddles the border between Baker-Snoqualmie National Forest, and Wenatchee National Forest. You'll want to coordinate with all 3 offices.


The Ptarmigan Traverse stretches along a steep ridge which traverses through some of the most incredible terrain in the lower 48 states. The characteristics that define the classic alpine environment present themselves around every corner and over ever col; precipitous glaciers, snowfields, towering peaks, boulder fields, flowering alpine meadows, crystal clear and cold alpine lakes, expansive views, bipolar weather, marmots, and the occasional mountain goat are ever present along the Ptarmigan Traverse.

Some of the best moments of this trip are:

Cascade Pass: The first time you get a hint at the true enormity of the mountains here, looking down the cascade river valley. While taking in the view down the valley to the east, don't forget to turn around and admire the intimidating north face of Johannesburg to your west.

Kool Aid Lake: The first Bivouac site (unless you use the optional short stop on day 1 at Cascade Pass). From this gorgeous alpine lake, you'll have an incredible photo opportunity to get Mt. Formidable, Arts Knoll and Kool Aid Lake in the same frame. This bivouac site is located on the edge of an incredible steep slope that drops a couple thousand feet to the valley below with unobstructed views.

Middle Cascade Glacier: This is the first big glacier of the route, and it is a beautiful jumble of steep falling seracs and crevasses. The run passes safely above the icefall, off the galcier, giving you plenty of photo opportunities. Above the icefall, the run moves on to the smoother upper glacier to the equally incredible views from Spider-Formidable Col.

White Rock Lakes: Unbelievable bivouac site. Between the unobstructed views of Dome Peak, (among others), a perfectly clear blue alpine lake, the perfectly situated bivouac area, and the sound of waterfalls, this was my favorite stop of the route. This is the last bivouac site of the trip in the high alpine above the treeline.

Need to Know

Even in perfect conditions I recommend bringing the following on top of your ultralight backpacking gear:
- 30m 'glacier' rope per two people or 60m lightweight (8-9mm max) single rope per 3 people.
- Nuts 1-10 and a single rack of cams .1-2. Will probably never use, but if you get lost/off route and need to rappel down, it can make you a safe anchor.
- Lots of food, don't get malnourished.
- Crampons - ultralight aluminum would be fine
- 1 snow picket minimum, per 3 people if the group is large
- 2 ice screws minimum, per 3 people if group is large
- Basic climbing accessories (belay/rappel device, pulley, cordage for crevasse rescue prusiks, etc.

Groups do this trip without this gear, relying on their route-finding and weather forecast to maximize the odds that they wont need it. So, use your best judgement!

Runner Notes

It has been run before, but do so at your own risk.


This is a multi-day alpine ridge traverse off trail which takes 5-8 days depending on the desired intensity and 'extracurricular' activities. This "trail" rides a fine line between climbing and backpacking. In some conditions, this can be done as a very strenuous backcountry wilderness trek. However, in challenging conditions this is a serious alpine mountaineering endeavor.

The true allure of this trip is the adventure, and as such, I wont spoil it by giving an endless list of turn by turn directions :) Rather, I'll give you some key waypoints you'll want to aim for so you don't end up stuck in seriously technical terrain. The term "col" is the low saddle point along a ridge connecting two mountains, it will get used a lot in the directions.

To get to the start:
Go to the Cascade Pass to Sahale Arm junction, and go south, off trail from there. Now you'll route-find your way south from lake to lake until you end at Cub Lake.

Major Waypoints:
1: Cache Col, have to cross over the ridge here.
2: Kool-Aid Lake, Bivouac #1
3: The red ledges (runs under Arts Knoll) - very narrow and exposed ledge that must be crossed, watch your footing! It is a little intimidating if you aren't a climber, but I promise it is the least technical way to go.
4: Spider-Formidable Col - above middle cascade glacier, its the only non-technical way to cross the ridge
5: Ying-Yang Lakes, Bivouac #2
6: Le Conte Glacier and Sentinel / Old Guard Peaks: The easiest way to cross onto South Cascade Glacier is at the smooth western crossover point of Le Conte Glacier north of these two peaks
7: South Cascade Glacier Col, just west of Lizard Mountain, the crossing point to access White Rock Lake, Bivouac #3
8: Spire Point, the col just east of spire point is the safest place to cross south between the Spire and Dana glaciers.
9: Cub Lake, Bivouac #4
10: Bachelor Creek / Downey Creek junction - you made it, you have reached a maintained trail again! You'll be so glad to see this well-maintained trail, after the unbelievably rough and strenuous bushwhack along bachelor creek.

Key points before you consider doing this trail:

1. There are glaciers and mountainous terrain. You and your party will need to know how to self arrest and conduct a crevasse rescue. The slopes are never incredibly steep, nor are there serious crevasse fields like on Rainier/Baker etc. In ideal conditions, the snow is very easy to traverse without crampons. However, you can't assume these perfect conditions will exist. Know your glacier and snow travel skills and bring the appropriate equipment. The route has been soloed before, but use your best judgement.

2. There is no cell coverage and you may not see another person the whole trip. Don't attempt this route if your wilderness self-care skills are not up to speed. Minor issues such as malnutrition, a sprained ankle, dehydration, or an infection can all lead to an expensive helicopter rescue (if you have a satellite phone to even call for one) or many days alone while your buddies walk 2-4 days to get help.

3. This is extremely physically demanding. The route calculator here shows 15,281ft ascent, but my actual GPS track, with all the intermediate ups and downs was almost 30,000ft. Find a 4,000ft ascent route, and give it a try with a 6-day backpacking load. Then think about doing that 5-8 days in a row. There are no easy ways out of this trek, so once you get 2-3 days into it, you are committed, you can't quit. If you can't pack for 6 days of this type of travel under 55lbs, consider buying lighter gear.

4. There are no trail markings. A rut has been established over time, but you need very good route finding skills, map reading, navigating off-terrain features, maneuvering around objective mountain hazards, etc. Bring your map and compass even if you have a GPS. If you get off route it will become technical mountain climbing.

Flora & Fauna

Marmot, Mountain Goats, Deer, Mosquitoes, Bears down low, and all variety of delicate alpine plants. Leave no trace!

History & Background

Basic Wiki Background:
The first traverse took 13 days in July 1938. The group consisted of four members of the Ptarmigan Climbing Club: Bill Cox, Calder Bressler, Ray W. Clough, and Tom Myers. The second traverse was in 1953 and consisted of Dale Cole, Bob Grant, Mike Hane, Erick Karlsson and Tom Miller. Miller took high-quality photos of the peaks, valleys, glaciers, and lakes, which were later published in a book by The Mountaineers. The book, called The North Cascades, was published in 1964 and proved instrumental in the bid to create the North Cascades National Park.

The route is named after the alpine bird of the same name. The "p" is silent and is pronounced "TAR-mig-an".

Coleman Leuthy and others made the third successful traverse of the route in the late 1950s. Today the route is a common goal of Cascade Range mountaineers.

There are tons of great peaks along the route, so take more than 5 days, bring your gear, and see how many you can climb!


Shared By:

Nate D with improvements by Logan Jackson

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Itswoot Ridge, White Rock Lakes, and Dome Peak along the Ptarmigan Traverse
Oct 11, 2016 near Stehekin, WA
Kool Aid Lake Bivouac site on the Ptarmigan Traverse.  Johannesburg in the right side background.
Oct 11, 2016 near Diablo, WA
Le Conte Mountain seen from the Ying Yang lakes bivouac site along the Ptarmigan Traverse.
Oct 11, 2016 near Stehekin, WA
Le Conte Mountain and glacier seen from Spider-Formidable col on the Ptarmigan Traverse.
Oct 11, 2016 near Stehekin, WA
Kool-Aid Lake, Arts Knoll and Mt. Formidable.  Taken from the bivouac site at Kool Aid lake on the Ptarmigan Traverse.
Oct 11, 2016 near Diablo, WA
Mt. Formidable.  The Red ledges on the left in the shadows
May 12, 2019 near Diablo, WA


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Jul 8, 2018
Damien Scott