The Great Ice Age Floods: Nature's Power and Beauty in Northwestern Landscapes
Discover your inner geologist and hear the divided history behind the National Park Service’s Geologic Trail as you explore and learn about the region’s stunning glacial landscapes.
Rating (5)
Program No. 9695RJ
6 days
Starts at
Getting There
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At a Glance

Rugged scablands, rippling loess hills, high basalt plateaus and plunging river canyons make up the Northwest’s dramatic landscapes. Only recently have scientists accepted what was once thought to be an outrageous tale of how they came to be. Follow the path of The Great Ice Age Floods across Washington and learn why the National Park Service is establishing a Geological Trail here. Touch the land yourself and step back to wonder at nature’s force.
Activity Level
Walking one-half mile a day; one hike is one mile over uneven terrain. Optional longer hikes.

Best of all, you'll ...

  • Discover how the glacial dam that burst from Lake Missoula, located over what is now western Montana, scoured the Northwest as it plunged seaward.
  • Follow the path of these Great Ice Age Floods across Washington to the 10 million year old basalt cliffs of Wallula Gap.
  • Study J Harlen Bretz's 1923 floods theory and learn why he was banished from geological circles — only to be vindicated some 30 years later.
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