Named for Chief Moses, this town was also formed by glacial floods, created during the last Ice Age, between 12,000 and 20,000 years ago. The 500-foot basalt cliffs offer some of the most geologically dramatic landscapes in Washington. Moses Coulee is one of the largest and most intact areas of shrub-steppe habitat remaining in the state. The Nature Conservancy protects a 3,588-acre portion of the area, known as the Moses Coulee Preserve.
The highway at first descends gently along the coulee’s eroded upper walls, serpentines along a manmade shelf blasted from solid cliffs, then levels off across the coulee floor. Nearly every color in the spectrum appears with the change in seasons and the play of light. Moses Coulee was created
Leaving the coulee, the highway dips up and down through waving fields of wheat to the Waterville plateau.