Ice Age Floods National Geologic Trail


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.

To Trail Headquarters from Spokane Take I-90 West At Exit 277, merge onto US-2 toward Davenport/Fairchild AFB/Spokane Airport Just past Wilbur, turn right onto WA-21 Stay left onto Highway 174 Turn right onto WA-155 Stay on WA-155 past Grand Coulee Dam and into the town of Coulee Dam Cross the Columbia River and continue on WA-155 Turn right onto Crest Drive and follow up the hill. The HQ Office is located on the left

  • Guided Tours
  • Self-Guided Tours - Walking
  • Self-Guided Tours - Auto

  • Tragic Events
  • Floods
  • Geology

Green Monarch Ridge

Green Monarch Ridge by Lake Pend Oreille ID

Green Monarch Ridge by Lake Pend Oreille ID

Steamboat Rock

Large butte with lake in the foreground

Steamboat Rock State Park, Washington

Banks Lake

Steamboat rock in the foreground with Banks Lake in the distance

Banks Lake view from Steamboat Rock

Dry Lakes

Dry Lake lake bed and falls blanked with snow.

Dry Lake lake bed and falls in winter

Dry Falls

A overhead shot of the Dry Falls area

A beautiful shot from the ledge near the visitor's center in the Dry Falls area.