The approach is the same as for the SE Buttress Route.
Once at the base of the SE Buttress, the Mountaineers Route is the sandy slope covered with weather-beaten trees to the right (north). Climb this class 2 slope to the top of Cathedral's north ridge, following any of several use trails (these are pretty sloppy and poorly defined). At the ridge, drop down about 30 feet and traverse over towards the west ridge, between the summit and Eichorn Pinnacle. This is a tricky section over some class 3 sloped slabs. Follow some large cracks in the slabs for the easiest route. Don't traverse all the way to the west ridge, instead head diagonally up towards some mangled trees on the north side of the west ridge. Staying north of the ridge, climb up towards the base of the summit blocks on the west side. Traverse around the summit blocks to the right, onto the South Face of Cathedral. There is an easy 15-foot class 4 crack on the south side of the summit blocks that takes you to the summit, or just to the left is an alternate 10-foot crack of about equal difficulty that can also be used.
No gear needed. If uncomfortable with class 4 or an airy perch on the small summit, bring a rope to belay on the summit blocks.
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