THE DAUPHIN COUNTY LAND BRIEF
Land in the
Northern Shale Valleys setting.
Dauphin County has 524.9 square miles of land in Pennsylvania. 6 mapped landscape regions meet across Dauphin County: Northern Shale Valleys, Northern Sandstone Ridges, Triassic Lowlands, among others.
Long, roughly parallel ridges and valleys follow folded and faulted rock layers. Limestone valleys, sandstone ridges and other geologic contrasts produce varied terrain and numerous regional springs and caves.
Regional context: Ridge and Valley ↗ · Regional mapping across the county footprint
Where the landscape changes
Dauphin County intersects 6 mapped regional units. The largest mapped shares are:
- Northern Shale Valleys51.1%
- Northern Sandstone Ridges32.7%
- Triassic Lowlands7.9%
- Northern Limestone/Dolomite Valleys4.5%
- Trap Rock and Conglomerate Uplands3.3%
Northern Piedmont in Dauphin County
Rounded low hills, open valleys and irregular plains form a transition between Appalachian highlands and the coastal plain. The underlying geology mixes metamorphic, igneous and sedimentary rocks.
Read the regional source ↗Finding your parcel within Dauphin County
The atlas lists 55 cities, towns, townships, and Census communities associated with Dauphin County, including Middle Paxton, East Hanover, Jackson. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Dauphin County by land and water
The Census records 33.2 square miles of water within Dauphin County, or 6% of its total area. That share is close to Dauphin County’s 6%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Dauphin County has 37.7 times the land area of nearby Wayne township (13.9 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Cumberland County, Juniata County, Lancaster County, Lebanon County, Northumberland County, Perry County, Schuylkill County, York County within Pennsylvania. A tract near one of these lines should be matched to the county identifier on its own records.

