1988 Map of North Sister

About this map

North Sister and Middle Sister dominate this high-elevation landscape, where glacial systems and volcanic formations meet along the crest of the Cascade Range. As of the late 1980s, the area reflects a transition from early mountaineering history to modern wilderness management, evidenced by commemorative sites like the Prouty Memorial Plaque and Bronaugh Memorial Plaque. The terrain is defined by active geology, including the Collier Glacier and the Ahalapam Cinder Field, alongside features like the Four In One Cone and Yapoah Crater.