THE JOHNSON COUNTY LAND BRIEF
Land in the
Rolling Loess Prairies setting.
Johnson County has 613 square miles of land in Iowa. 3 mapped landscape regions meet across Johnson County: Rolling Loess Prairies, Upper Mississippi Alluvial Plain, Eastern Iowa and Minnesota Drift Plains.
Glacial till plains and windblown loess hills make up the Western Corn Belt landscape. Near-level and rolling terrain are interspersed with steeper river valleys and hills.
Regional context: Western Corn Belt Plains ↗ · Regional mapping across the county footprint
Where the landscape changes
Johnson County intersects 3 mapped regional units. The largest mapped shares are:
- Rolling Loess Prairies85.1%
- Upper Mississippi Alluvial Plain13.5%
- Eastern Iowa and Minnesota Drift Plains1.4%
Interior River Valleys and Hills in Johnson County
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.
Read the regional source ↗Finding your parcel within Johnson County
The atlas lists 13 cities, towns, townships, and Census communities associated with Johnson County, including Iowa City, Coralville, North Liberty. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Johnson County by land and water
The Census records 10.1 square miles of water within Johnson County, or 1.6% of its total area. That share is close to Johnson County’s 1.6%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Johnson County has 2,357.7 times the land area of nearby University Heights city (0.26 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Benton County, Cedar County, Iowa County, Linn County, Louisa County, Muscatine County, Washington County within Iowa. A tract near one of these lines should be matched to the county identifier on its own records.

