The following is a list of known Keystone Markers sorted by county. Some are still extant, and others are now missing and only known through photographs and memories. Most of the markers that can still be found around Pennsylvania are the town name markers, though there are other varieties. Choose a county listed below to view a list of the markers located there.
Adams County
Allegheny County
Armstrong County
Beaver County
Bedford County
Berks County
Blair County
Bradford County
Bucks County
Butler County
Cambria County
Cameron County
Carbon County
Centre County
Chester County
Clarion County
Clearfield County
Clinton County
Columbia County
Crawford County
Cumberland County
Dauphin County
Delaware County
Elk County
Erie County
Fayette County
Forest County
Franklin County
Fulton County
Greene County
Huntingdon County
Indiana County
Jefferson County
Juniata County
Lackawanna County
Lancaster County
Lawrence County
Lebanon County
Lehigh County
Luzerne County
Lycoming County
McKean County
Mercer County
Mifflin County
Monroe County
Montgomery County
Montour County
Northampton County
Northumberland County
Perry County
Philadelphia County
Pike County
Potter County
Schuylkill County
Snyder County
Somerset County
Sullivan County
Susquehanna County
Tioga County
Union County
Venango County
Warren County
Washington County
Wayne County
Westmoreland County
Wyoming County