THE CLAY COUNTY LAND BRIEF
Land in the
Southern Illinoian Till Plain setting.
Clay County has 468.4 square miles of land in Illinois. 2 mapped landscape regions meet across Clay County: Southern Illinoian Till Plain, Wabash-Ohio Bottomlands.
Broad terraced river valleys contrast with wooded slopes and dissected glacial plains. Bottomland settings and upland oak landscapes occur close together across the Interior River Valleys and Hills.
Regional context: Interior River Valleys and Hills ↗ · Regional mapping across the county footprint
Where the landscape changes
Clay County intersects 2 mapped regional units. The largest mapped shares are:
- Southern Illinoian Till Plain95.6%
- Wabash-Ohio Bottomlands4.4%
Finding your parcel within Clay County
The atlas lists 18 cities, towns, townships, and Census communities associated with Clay County, including Harter, Stanford, Pixley. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Clay County by land and water
The Census records 1.18 square miles of water within Clay County, or 0.3% of its total area. That share is close to Clay County’s 0.3%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Clay County has 565.6 times the land area of nearby Louisville village (0.83 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Effingham County, Fayette County, Jasper County, Marion County, Richland County, Wayne County within Illinois. A tract near one of these lines should be matched to the county identifier on its own records.

