THE CUSTER COUNTY LAND BRIEF
Land in the
Southern Forested Mountains setting.
Custer County has 4,922.2 square miles of land in Idaho. 8 mapped landscape regions meet across Custer County: Southern Forested Mountains, Dry Gneissic-Schistose-Volcanic Hills, Dry Partly Wooded Mountains, among others.
A deeply cut mountainous plateau forms the Idaho Batholith. Granitic terrain supports conifer forests, while deep canyons introduce warmer settings with pine, shrubs and grasses.
Regional context: Idaho Batholith ↗ · Regional mapping across the county footprint
Where the landscape changes
Custer County intersects 8 mapped regional units. The largest mapped shares are:
- Southern Forested Mountains26.6%
- Dry Gneissic-Schistose-Volcanic Hills24.5%
- Dry Partly Wooded Mountains14.2%
- Dry Intermontane Sagebrush Valleys11.6%
- Barren Mountains8.1%
Middle Rockies in Custer County
Forested mountain ranges rise above grassy or shrubby intermountain valleys. The Middle Rockies combine alpine high country, partly wooded foothills and valleys supplied by mountain streams.
Read the regional source ↗Finding your parcel within Custer County
The atlas lists 5 cities, towns, townships, and Census communities associated with Custer County, including Lost River, Challis, Mackay. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Custer County by land and water
The Census records 16.4 square miles of water within Custer County, or 0.3% of its total area. That share is close to Custer County’s 0.3%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Custer County has 76,909 times the land area of nearby Clayton city (0.06 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Blaine County, Boise County, Butte County, Elmore County, Lemhi County, Valley County within Idaho. A tract near one of these lines should be matched to the county identifier on its own records.

