THE PLYMOUTH COUNTY LAND BRIEF
Land in the
Loess Prairies setting.
Plymouth County has 862.8 square miles of land in Iowa. 4 mapped landscape regions meet across Plymouth County: Loess Prairies, Steeply Rolling Loess Prairies, Western Loess Hills, among others.
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
Plymouth County intersects 4 mapped regional units. The largest mapped shares are:
- Loess Prairies74.2%
- Steeply Rolling Loess Prairies14.7%
- Western Loess Hills9.5%
- Missouri Alluvial Plain1.6%
Finding your parcel within Plymouth County
The atlas lists 12 cities, towns, townships, and Census communities associated with Plymouth County, including Sioux City, Le Mars, Kingsley. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Plymouth County by land and water
The Census records 0.84 square miles of water within Plymouth County, or 0.1% of its total area. That share is close to Plymouth County’s 0.1%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Plymouth County has 1,656.1 times the land area of nearby Merrill city (0.52 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Cherokee County, O'Brien County, Sioux County, Woodbury County within Iowa. A tract near one of these lines should be matched to the county identifier on its own records.

