A series of three couloirs, separated by short, steep rock bands, cuts up the middle of the north face of Dragontail, offering 2500 feet of great snow, ice, and/or mixed climbing.
Colchuck Lake sits in view below and glimpses of Cashmere Mountain and other Cascade peaks keep one company on the route, but the couloirs are deep so the exposure is never overwhelming.
This route is somewhat popular and generally gets climbed by one variation or another several times each spring. The specific line taken, time required, and type of climbing encountered are entirely conditions dependent however, so that very few climbs of triple couloirs are the same. Triple Couloirs could and likely has been climbed in every condition imaginable, and has even been skied, and it is up to the climber to decide what sort of ice and snow coverage is acceptable for their attempt on any of the established variations.
Hike the Stuart Lake trail from the end of Eightmile Road to its junction with the Colchuck Lake trail and follow this to Colchuck Lake. If the lake is frozen, cross it directly to possible campsites either on or near the lake under the north side of Dragontail. Water can be obtained by chopping through the ice of the lake, as it is deep and never freezes more than a few feet thick.
During the time of year when the climb is in best condition Eightmile road leading to the Stuart Lake trailhead from Icicle Creek Road may be either snowed-in, gated, or both. This will add four miles and about 1000 feet of vertical each way.
This climb can be done car to car in a long day, but is usually only reasonable if Eightmile road is open to the trailhead and you can travel all the way to Colchuck Lake without any flotation issues.
The first couloir of the route, called the Hidden Couloir due to the lack of a view of it from Colchuck Lake, starts at about 6400 feet in elevation directly above the south end of the lake. This couloir trends southward for about 800 vertical feet at a ~45-degree slope and usually retains snow until mid summer. Following this slot past an initial steep step to near its end, one will encounter a steep rock band separating the hidden couloir from the second couloir which can offer two to three ropelengths of 70-80 degree ice. The condition of this section, locally referred to as the Runnels, can be evaluated from Colchuck Lake; look for complete coverage of the rock band directly below the bottom of the second couloir which cuts straight up the middle of the face. Without ice, this band will consist of steep slabs with limited protection and is generally not recommended. The Runnels generally feature the most climbable ice in Spring after a significant number of daily cycles of freezing and thawing or after a wet, cold storm plasters the mountain.
There are two reasonable alternatives if the Runnels do not look appealing:
1) Continue climbing up the Hidden Couloir for about 200 feet past the Runnels and then follow a shallow corner system up to an open snow field roughly even with the bottom of the second couloir. This variation generally offers very reasonable and well-protected mixed climbing, and possibly better ice climbing than one would find in the Runnels. From the snow field make your way back climber's left to the edge of the Triple Couloirs and either downclimb, 5.8, or rappel 10 meters or so into the bottom of the second couloir. One will likely find fixed rappel anchors here from previous parties.
2) Continue climbing up the Hidden Couloir and follow it all the way out onto the North Face. Climb several hundred feet of mixed terrain up to 5.7 trending climber's left all the way to the bottom of the third and final couloir.
Continuing from the bottom of the second couloir make your way straight up another ~45 degree slot for several hundred feet. The couloir branches here, continue to climber's right if you wish to finish on the third couloir. The second and third couloir are separated by another short, steep band that can offer anything from easy, thick ice to thin, poorly-protected mixed climbing. The third couloir slashes behind the prominent feature called the Fin up to an open slope a couple hundred feet below the summit. Follow the open slope to the summit and descend via the Snow Creek Glacier to Asgard Pass and on down to Colchuck Lake.
The route is long, but most climbers will pitch out only 3 or 4 pitches, efficient simul-climbing is key.
In order to be prepared for a variety of conditions bring ice tools, crampons, rock pro to 2 inches with an emphasis on pins, some ice screws, and pickets.
Required reading for climbing triple couloirs, here.
It's been skied, read about it here.
Complete view of Triple Couloirs from the air, here,
courtesy of the incomparable John Scurlock.