Climactic Eruption (7,700 years ago)

Eruption History for Mount Mazama and Crater Lake Caldera

The climactic eruption of Mount Mazama devastated the terrain for tens of kilometers from the volcano, sent pyroclastic flows as far as 70 km (43 mi) down every valley heading on the volcano, and produced ash fall throughout much of the Pacific Northwest and parts of southern Canada.

Mount Mazama is one of the major volcanoes of the Cascades Arc.