Podcast | How Mount Mazama blew its top and became Crater Lake

Crater Lake wasn’t always a lake. Knute Berger tells of when a blast 50 times the size of Mount St. Helens’ blanketed the PNW in ash. 

eruption of Mount Mazama drawing

A rendering of the eruption of Mount Mazama. (The National Park Service)

Crater Lake National Park in southern Oregon is known for its crown jewel: a brilliantly blue and very deep alpine lake. But some 8,000 years ago, this lake was a mountain. 

Then the mountain erupted, blowing its top and layering ash so far afield that it impacted wildlife in Canada. Indigenous people carry oral traditions that share what it was like to witness the blast. 

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Crosscut’s resident historian Knute Berger unearthed this history in a recent episode of the Mossback’s Northwest video series, but there is more left to uncover. 

In this episode of Mossback, Berger joins co-host Stephen Hegg to more deeply understand the geologic history of the blast and the cultural history of what eventually became known as Mount Mazama. They also discuss the chance of this or any other volcano in the Pacific Northwest blowing again — and what impact that could have on all of us. 

About the Hosts

Knute Berger

Knute Berger

Knute “Mossback” Berger is Crosscut's Editor-at-Large.

Stephen Hegg

Stephen Hegg

Stephen is formerly a senior video producer at Crosscut and KCTS 9. He specialized in arts and culture.