THE MASON COUNTY LAND BRIEF
Land in the
Sand Area setting.
Mason County has 539.4 square miles of land in Illinois. 3 mapped landscape regions meet across Mason County: Sand Area, Illinois/Indiana Prairies, Upper Mississippi Alluvial Plain.
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.
Regional context: Central Corn Belt Plains ↗ · Regional mapping across the county footprint
Where the landscape changes
Mason County intersects 3 mapped regional units. The largest mapped shares are:
- Sand Area66.8%
- Illinois/Indiana Prairies18.6%
- Upper Mississippi Alluvial Plain14.6%
Interior River Valleys and Hills in Mason 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 Mason County
The atlas lists 23 cities, towns, townships, and Census communities associated with Mason County, including Bath, Havana, Manito. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Mason County by land and water
The Census records 24.2 square miles of water within Mason County, or 4.3% of its total area. That share is close to Mason County’s 4.3%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Mason County has 15 times the land area of nearby Sherman township (36 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Cass County, Fulton County, Logan County, Menard County, Schuyler County, Tazewell County within Illinois. A tract near one of these lines should be matched to the county identifier on its own records.

