South Sister 10,363 feet (3,159 m)
Stratovolcano
en.wikipedia.org/wiki/Three_Sisters_(Oregon)
Broken Top
en.wikipedia.org/wiki/Broken_Top
Rock Mesa Obsidian Flow
Obsidian flow created from flank eruption of South Sister approximately 2000 years ago.
www.
South Sister
Photo of South Sister by
Photo of South Sister by
