From NPR
Hells Canyon is the deepest river canyon in the United States. Now scientists have solved the mystery of when it formed.
(Image credit: Matthew Morriss)
Hells Canyon, the deepest gorge in the U.S., is surprisingly young
Hells Canyon is the deepest river canyon in the United States. Now scientists have solved the mystery of when it formed.
(Image credit: Matthew Morriss)
