By editor
Sanders County
The Camas Prairie looks like a quiet, rolling grassland north of Missoula. But the topography here was bulldozed by catastrophe. At the end of the Pleistocene, the Cordilleran Ice Sheet blocked the Clark Fork River, backing up Glacial Lake Missoula to a depth of four thousand feet. When the ice dam failed, the unimaginable volume of water tore across the Camas Prairie, sculpting the gravel of the valley floor into massive ripple marks up to fifty feet high and half a mile long.
Visitor Access
This is a National Natural Landmark designated for viewing only. Much of the land containing the ripples is privately owned. The best way to read this landscape is to pull over on Montana Highway 28 or 382, where the sheer scale of the frozen, grassy echoes of the largest floods on Earth becomes visible.