This is a line that can be more risky to ski to than down. That is unless you bootpack it up… Coming from the Reed and Benson ridge is less work but the final approach is kinda tricky as you have to traverse from point 10,561 (the peak just north of Flagstaff Mountain) down a 40 degrees + slope that cliffs out (as in BIG cliffs) below you. Not the place you want to be caught in an avalanche or even any serious sluffing… In any case once you are in it, this is an impressive, scenic and delightful ski. You drop about 800 feet in the couloir and then an additional 900 in the “tube”.
The name can seem redundant as Couloir is French for Hallway but in this case Hallway is not primarily referring to a hallway but rather a play on Doug Hall’s last name. He was an avid backcountry skier and climber that died in 1997 when he got swept away by an avalanche while ice climbing in Provo Canyon.
The picture below gives a sense of what you have to go through to get to the Hallway from above but is not detailed enough to actually show you the way so don’t rely on this shot to find the entrance (click to enlarge).