THE JEFFERSON COUNTY LAND BRIEF
Land in the
Pittsburgh Low Plateau setting.
Jefferson County has 652.4 square miles of land in Pennsylvania. 3 mapped landscape regions meet across Jefferson County: Pittsburgh Low Plateau, Unglaciated High Allegheny Plateau, Uplands and Valleys of Mixed Land Use.
Rounded wooded hills and intervening valleys form an unglaciated plateau landscape. Valley floors contain much of the region's open land, contrasting with its more forested slopes.
Regional context: Western Allegheny Plateau ↗ · Regional mapping across the county footprint
Where the landscape changes
Jefferson County intersects 3 mapped regional units. The largest mapped shares are:
- Pittsburgh Low Plateau73.2%
- Unglaciated High Allegheny Plateau25.1%
- Uplands and Valleys of Mixed Land Use1.7%
North Central Appalachians in Jefferson County
Forest-covered plateau surfaces, high hills and low mountains are underlain by layered sedimentary rocks. Most of this region escaped continental glaciation, leaving deeply cut upland terrain.
Read the regional source ↗Central Appalachians in Jefferson County
A rugged, deeply cut plateau of sandstone, shale and related rocks supports extensive forest. High hills and low mountains distinguish this Appalachian landscape from smoother neighboring regions.
Read the regional source ↗Finding your parcel within Jefferson County
The atlas lists 35 cities, towns, townships, and Census communities associated with Jefferson County, including Warsaw, Washington, Eldred. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Jefferson County by land and water
The Census records 4.36 square miles of water within Jefferson County, or 0.7% of its total area. That share is close to Jefferson County’s 0.7%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Jefferson County has 23 times the land area of nearby Pine Creek township (28.3 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Armstrong County, Clarion County, Clearfield County, Elk County, Forest County, Indiana County within Pennsylvania. A tract near one of these lines should be matched to the county identifier on its own records.

