Start from Andrews Lake, 1mi. Southwest of Molas Pass, and 1.9 Mi. Northwest of Snowdon Pk.
There is a newly constructed trail (different than on the USGS Topo would indicate) that tours the West and South sides of Andrews Lake, then switchbacks the same general line Southward 3/4's of a mile to a faint grassy ridgeline at 11,000'. There are two small ponds noted on the map in this area, and the main trail heads Southwest, but you don't. Leave the main trail! Follow a faint hikers trail Southeast across a large meadow and into the forest. Cross a second meadow along its left side and follow the forest line to the foot of Snowdons Northwestern Morraine. The forested ridgerunners route to the the Northeast ridge takes off to the left here at about 11,600'. Work your way left along the foot of the morraine, until you find easy passage up it's steep (but short) foot. Once on the Morraine, the Northwest couloir is in full view. Work yor way up the broad morraine about 300 vertical feet to a broad flat boulder pile at the foot of the Couloir (12,060'). This is a good place to put on crampons and survey the route. You are about 800' below the col North of the summit. If conditions are poor, you can contour Northeast into a lesser angled and wider gully that ties into the Northeast ridge route at 12,600'. North facing slabs below the West Buttress overhang the couloir, and can drop snowmelt and rockfall on the route. Try to be up the lower two thirds of the route before the meltfall. This portion of the route graduates from 40-45 degrees. At two thirds height, you must move left 10 ft (3rd class rock) into the upper couloir. The upper couloir graduates from 50-60 degrees rapidly, but tops out after only 100 yards. in mid-June, the snow/ ice ended abruptly below an 8 foot (4th class rock move). Once on the ridge, follow the path of least resistance (2+) around the East side of the summit block to an easy finish (5 minutes). I chose not to downclimb the couloir, but followed the fine Northeast ridge route down (Class 3). On the way down, just below the col is the trickiest part. You may sit there and wonder about the route rating??? downclimb the sharp ridge (20 feet) and upclimb the first obstacle, half way up, there is a surprise ledge on the West side that brings you through a wedge and back on to the ridgline proper. The rest is easy...
No rock pro is needed on this route, but bring crampons and ice axe for sure. I (free) soloed the couloir while it was soft, but ice pro and a rope would be handy any earlier in the day, especially with partners...
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