The Glacier Mountaineering Society hiking group approaches a narrow spot on the east ridge of Rising Wolf Mountain, the result of a feature known as the Diorite Sill, an intrusion of igneous rock in the sedimentary rock of Glacier. This stretch is fun and solid Class 3 climbing to the left of the ridge crest, contouring above a steep snow field. Climb carefully through this stretch! Rising Wolf Mountain, Glacier National Park, Summer, 2006.

Digital photo by Aaron Johnson