THE LEWIS COUNTY LAND BRIEF
Land in the
Nez Perce Prairie setting.
Lewis County has 478.8 square miles of land in Idaho. 5 mapped landscape regions meet across Lewis County: Nez Perce Prairie, Lower Clearwater Canyons, Grassy Potlatch Ridges, among others.
Basalt underlies this dry plateau of grassland and sagebrush. Windblown soils cover some uplands, while ancient flood paths exposed rock across the region's scabland terrain.
Regional context: Columbia Plateau ↗ · Regional mapping across the county footprint
Where the landscape changes
Lewis County intersects 5 mapped regional units. The largest mapped shares are:
- Nez Perce Prairie56.5%
- Lower Clearwater Canyons18.3%
- Grassy Potlatch Ridges11.6%
- Canyons and Dissected Uplands7%
- Canyons and Dissected Highlands6.6%
Northern Rockies in Lewis County
The Northern Rockies contain rugged ranges, glacial lakes and mixed conifer forests. Moist Pacific influences reach some inland valleys, producing forest communities unlike the drier mountain regions farther south.
Read the regional source ↗Blue Mountains in Lewis County
The Blue Mountains combine open mountain ranges and dissected volcanic uplands. The Wallowa and Elkhorn high country includes older granitic and metamorphic rocks above the surrounding lava landscape.
Read the regional source ↗Finding your parcel within Lewis County
The atlas lists 5 cities, towns, townships, and Census communities associated with Lewis County, including Kamiah, Craigmont, Nezperce. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Lewis County by land and water
The Census records 0.9 square miles of water within Lewis County, or 0.2% of its total area. That share is close to Lewis County’s 0.2%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Lewis County has 616.2 times the land area of nearby Craigmont city (0.78 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Clearwater County, Idaho County, Nez Perce County within Idaho. A tract near one of these lines should be matched to the county identifier on its own records.

