Global Volcanism Program | Image GVP-03102
South Sister is the highest of the Three Sisters volcanoes and is seen here above Green Lake from the west flank of Broken Top volcano. The bare slope to the far-left is the Newberry lava flow, the northernmost of a series of SE-flank obsidian domes and flows.
Photo by Lyn Topinka, 1985 (U.S. Geological Survey).
This image is made available as a Public Domain Work, but proper attribution is appreciated.