THE PEORIA COUNTY LAND BRIEF
Land in the
Western Dissected Illinoian Till Plain setting.
Peoria County has 618.7 square miles of land in Illinois. 4 mapped landscape regions meet across Peoria County: Western Dissected Illinoian Till Plain, River Hills, Illinois/Indiana Prairies, among others.
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
Peoria County intersects 4 mapped regional units. The largest mapped shares are:
- Western Dissected Illinoian Till Plain54.3%
- River Hills18%
- Illinois/Indiana Prairies17.8%
- Upper Mississippi Alluvial Plain10%
Central Corn Belt Plains in Peoria County
Glaciated plains historically supported tallgrass prairie mixed with oak and hickory woodland. Dark prairie soils and broad farming landscapes distinguish much of the Central Corn Belt.
Read the regional source ↗Finding your parcel within Peoria County
The atlas lists 41 cities, towns, townships, and Census communities associated with Peoria County, including Peoria, Peoria City, Limestone. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Peoria County by land and water
The Census records 11.6 square miles of water within Peoria County, or 1.8% of its total area. That share is close to Peoria County’s 1.8%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Peoria County has 17 times the land area of nearby Rosefield township (36.4 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Fulton County, Knox County, Marshall County, Stark County, Tazewell County, Woodford County within Illinois. A tract near one of these lines should be matched to the county identifier on its own records.

