THE ONONDAGA COUNTY LAND BRIEF
Land in the
Ontario Lowlands setting.
Onondaga County has 778.4 square miles of land in New York. 3 mapped landscape regions meet across Onondaga County: Ontario Lowlands, Finger Lakes Uplands and Gorges, Glaciated Low Allegheny Plateau.
Glacially shaped lowlands and irregular plains border the Great Lakes and adjacent hills. The lakes influence regional weather, while local landforms reflect both glacial deposits and former shorelines.
Regional context: Eastern Great Lakes Lowlands ↗ · Regional mapping across the county footprint
Where the landscape changes
Onondaga County intersects 3 mapped regional units. The largest mapped shares are:
- Ontario Lowlands64.2%
- Finger Lakes Uplands and Gorges32.9%
- Glaciated Low Allegheny Plateau2.9%
Northern Allegheny Plateau in Onondaga County
Rolling hills, broad valleys and low mountains are mantled by glacial deposits. Sandstone, shale and siltstone underlie a mix of open land and woodland across the northern plateau.
Read the regional source ↗Finding your parcel within Onondaga County
The atlas lists 48 cities, towns, townships, and Census communities associated with Onondaga County, including Pompey, Lysander, Onondaga. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Onondaga County by land and water
The Census records 27.2 square miles of water within Onondaga County, or 3.4% of its total area. That share is close to Onondaga County’s 3.4%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Onondaga County has 13.5 times the land area of nearby Onondaga town (57.6 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Cayuga County, Cortland County, Madison County, Oswego County within New York. A tract near one of these lines should be matched to the county identifier on its own records.

