One of the premier ski mountaineering lines in Colorado.



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The Snake Couloir splits the North Face of Mt.

Sneffels, which itself dominates all views of the San Juan range from the North.

This impressive peak is one of the most photographed peaks in Colorado, and requires a technical ascent in typical winter conditions.

The descent starts with a rappel directly off the summit and into the couloir, and from here, a dog-legging couloir with a very steep and narrow choke lead to Blaine Basin below.

This line is one of the steepest, longest, and sustained lines in Colorado, and is a classic descent for accomplished ski mountaineers.

The day starts in Yankee Boy Basin, which is accessible from Camp Bird Road in Ouray.

Usually, the gated upper part of the road opens in late April or early May, and before this opening, skiers have to approach from the Skylight parking area, which adds a couple hours to the approach.

As such, most ski descents of the Snake Couloir occur after the gate opens and the road is plowed to Yankee Boy Basin.

The approach through Yankee Boy takes skiers past many other appetizing ski terrain, but Mt.

Sneffels dominates the skyline.

After climbing up to the Lavender Col, and from there up the Lavender Couloir, the route turns left through a small cleft in the rock that requires a class 4 move to surmount, which is awkward with skis.

Some may want to rope up for this move.

Once through this notch, the route follows a snow arete to the summit.

It is a spectacular climb in winter conditions, and the summit ridgeline feels like a stairway to heaven.

From the summit, the 360-degree views of the San Juans are unforgettable.

Build a rappel anchor on the summit, commonly by slinging a large boulder which may require digging through snow to find.

Rappel off the north side of the summit, up to 25 meters (80 feet), and into the couloir. The run starts with an exposed, open snow ridge, then drops down and left into the couloir itself, which steepens to 45 degrees before doglegging to the right.

A fall here would be fatal, as shallow, jagged rocks pepper the inside of the curve, and high rock walls line the couloir.

A small snow col to the skiers left at the dogleg offers a protected spot to regroup.

From here, ski down and into the second half of the couloir, which bends to the right, steepens to 50 degrees, and narrows to little more than a ski width.

Once through this narrow section, the angle lessens, the walls open up, and the apron comes quickly.

Glorious sheltered turns for over 1,500 vertical feet into Blaine Basin complete this excellent ski run.

From here, don skins and reascend the east fork of Blaine Basin to Lavender Col and ski down Yankee Boy basin back to the car.

Late in the spring, the road to Blue Lakes trailhead melts out, and a car can be left here to prevent the need to reascend to Lavender Col, allowing skiers to descend Blaine Basin and Wilson Creek, but the car shuttle is lengthy, and some bushwhacking is involved.

A return tour to Yankee Boy basin requires 5,500’ of ascent and descent, and is the more aesthetic option.