An Expert’s Guide to Big Couloir at Big Sky

big couloir lone peak

At Big Sky, Lone Peak is by far the most famous feature of the resort. And on Lone Peak, no run is as iconic as Big Couloir.

In this post, I’ll share everything you need to know about Big Sky’s iconic Big Couloir.

What is Big Couloir at Big Sky?

big couloir big sky resort

Big Couloir is one of the most challenging, steepest lines at Big Sky Resort.

A lot of ski resort’s marketing materials throw around the terms “challenging” and “steep” but The Big is really no joke in this area. Remember, this is a mountain known for its legitimate tripled black (yes, triple!) terrain, so when Big Sky says this run is a challenge, they mean it!

The line shoots right down the middle of the front face of Big Sky’s iconic Lone Peak. This means that just about wherever you are at the resort, Lone Peak, and its “Is that actually a ski run?” line that is Big Couloir, stares visitors in the face.

This is most apparent at the original tram line. For years, skiers waiting for the tram would have a front-row seat to this cliff of a ski run, and the brave souls who dared ski down it. The view is enough to give even the gnarliest skiers a bit of butterflies in the stomach!

big couloir tram view
Big Couloir from underneath the Tram (just right of the tram in photo)

3 Things You Need to Know Before Dropping Big Couloir

If you’re thinking about tackling The Big, make sure you’ve considered these unique facts about the famous run.

1. Ski Patrol Requires You to Check In

big couloir meme

You can’t just traverse over to Big Couloir, point them down the hill, and send it.

No… as we discussed earlier, this run is really, truly, no joke. So, Ski Patrol guards it carefully to make sure they don’t have daily disasters on their hand.

Before entering Big Couloir, you first have to check into the Ski Patrol outpost at the top of the tram. This gives you a sign-out time which limits the run to two skiers every 15 minutes.

2. You must bring avalanche gear

Speaking of ski patrol check in, they don’t let you through until they check that you have a working avalanche beacon. (A common rumor is that you need a shovel and probe as well, but as of recently, you only need the beacon.)

3. You need a partner

Remember, two skiers every 15 minutes. That means if you were planning on going solo, you’ll need to round up a partner to come with you.

(Ski patrol requires this for safety reasons.)

If you can’t find anyone crazy enough to drop into this run with you, Big Sky does offer Tram Guides. Be warned though, they ain’t cheap. And they’ll require you to book the more expensive full-day option if you’re planning on skiing The Big, in order to ensure there’s enough time for the ski patrol sign-out times.

So, how difficult is Big Couloir at Big Sky?

In case the avalanche requirements and ski patron sign out weren’t obvious enough, Big Couloir isn’t for anyone beyond legitimate experts!

The terrain is a legitimate “no-fall zone” as this unfortunate skier learned the hard way:

Why? The Big is legitimately one of the steepest in-bound runs in North America. But more importantly, there’s maybe no other in-bounds run that combines this level of steepness for this long of a run.

Speaking of which…

How steep is Big Couloir?

Big Sky officially claims that Big Couloir has a steepness of 50 degrees. Other sources, such as which uses topographical and GPS data, calculates the run at a max steepness of 48 degrees.

That difference is splitting hairs though, especially when you consider that double black terrain at most ski resorts ranges anywhere from 30-35 degrees of steepness.

Yes, Big Couloir is steep!

And how long Big Couloir?

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3D Rendering of Big Couloir from

Big Couloir is about half a mile long and descends over 1,300 vertical feet.

Along the way, the run takes a slight right hand turn, followed by a left, and both sides are corralled by jagged rock croppings. Hence, no falling!

Once through the couloir, the terrain opens up in to a big, wide powder field.

A recommended expert progression before considering Big Couloir

According to the man himself, Dan Egan, who runs Big Sky’s Steeps Camps for aspiring skiers who want to tackle Big Couloir, you can practice for The Big by focusing on the following runs off Challenger Lift:

  1. Moonlight into Big Rock Tongue
  2. Then Big Rock Tongue Main Chute
  3. Then Cold Spring off the Headwaters zone

Interestingly, none of those practice runs are Triple Black rated like The Couloir, so do recognize that these don’t quite simulate the sheer length and consequences of the real deal.

If unsure, you should definitely pick the ski patroller’s brains when you enter the patrol outpost; these guys are the true experts of the terrain and can offer advice and insight on the run’s current conditions.