The Dana Couloir, given it's moderate angle, straight / wide shape, and close vincinity to Tioga Road is one of the most popular moderate snow / ice climbs and spring ski / snowboard descents in the Sierra. It remains popular from when Tioga Road opens in the spring through the autumn when it becomes more serious ice undertaking. Here are some photos showing the couloir's various conditions in 2002:
The easiest way to approach Dana Couloir is via Glacier Canyon Trail. Follow the Glacier Canyon Route to "upper Dana Meadows" and then continue southeast up the valley to Dana Lake from where you will be able to see the couloir. Cross and head up the Dana Glacier to enter the Couloir proper.
An alternate route, if you just want to ski down, is to hike up the West Slope from the YNP Tioga Pass Entrance Station and enter the couloir from the southeast ridge. However, it is advisable to climb the couloir so you can check the snow conditions.
The 1,200 foot Dana Couloir is a straight-forward snow / ice climb that approaches 40 degrees and tops out at 12,400 feet. To reach the summit make a short hike (no trail) once you attain the southeast ridge. Late in the season, the bergscrund forms at the lower end of the couloir between the two rock formations making the ascent more difficult (this was manageable w/o pro on June 24, 2001). When conditions warrant protection, this route can be done in "four pitches from the bergschrund to the notch" (Ref: forjan).
It is also possible to do a rock scramble (class 3) to the north of the couloir, however, the rock here is extremely loose.
This route gets progressively icier through the year. During the spring and early summer, a mountaineering ice axe and crampons are all that is generally required or advisable. A second ice axe or tool is desirable when the route is icy (e.g. June 24, 2001). By late fall, the route typically becomes a true ice climb making ice tools and protection using ice screws desirable.
The best time to ski is between April and early June after CA SR-120 has been plowed to Tioga Pass. Skiing earlier in the season is possible however you will need to ski in. The Tioga Pass Resort is a cozy place to stay if you want to do this. Many people ski the Ellery Bowl (also Double Black Diamond) off of Dana Plateau in the same trip.
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