Ice Age Floods of Change

At the end of the last Ice Age, 18,000 to 15,000 years ago, an ice dam in northern Idaho created Glacial Lake Missoula stretching 3,000 square miles around Missoula, Montana. The dam burst and released flood waters across Washington, down the Columbia River into Oregon before reaching the Pacific Ocean. The Ice Age Floods forever changed the lives and landscape of the Pacific Northwest.

Map of the Ice Age Floods across the Pacific Northwest

Ice Age Floods National Geologic Trail

Map of the Ice Age Floods across the Pacific Northwest

Columbia Rive runs through

Lean about the Trail

Learn the story of the Missoula Floods.

basalt hillside has green trees in front of it.

Places To Go

Explore Ice Age Floods National Geologic Trail and the 4 states which the Missoula Floods flowed through.

Last updated: March 30, 2023

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Contact Info

Mailing Address:

Program Manager
Ice Age Floods National Geologic Trail
1008 Crest Drive

Coulee Dam, WA 99116

Phone:

(509) 237-9722

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