Delaware Valley

Regions of Pennsylvania
Piedmont \| South Mountains \| Ridge-and-valley Appalachians \| Allegheny Plateau
Delaware Valley (Philadelphia metropolitan area) \| Northern Tier \| New York metropolitan area
Largest Cities
Allentown \| Altoona \| Bethel Park \| Bethlehem \| Chester \| Drexel Hill \| Erie \| Harrisburg \| Lancaster \| Levittown \| Mount Lebanon \| New Cumberland \| Norristown \| Penn Hills \| Philadelphia \| Pittsburgh \| Reading \| Scranton \| State College \| Wilkes-Barre
Counties
Adams \| Allegheny \| Armstrong \| Beaver \| Bedford \| Berks \| Blair \| Bradford \| Bucks \| Butler \| Cambria \| Cameron \| Carbon \| Centre \| Chester \| Clarion \| Clearfield \| Clinton \| Columbia \| Crawford \| Cumberland \| Dauphin \| Delaware \| Elk \| Erie \| Fayette \| Forest \| Franklin \| Fulton \| Greene \| Huntingdon \| Indiana \| Jefferson \| Juniata \| Lackawanna \| Lancaster \| Lawrence \| Lebanon \| Lehigh \| Luzerne \| Lycoming \| McKean \| Mercer \| Mifflin \| Monroe \| Montgomery \| Montour \| Northampton \| Northumberland \| Perry \| Philadelphia \| Potter \| Schuylkill \| Snyder \| Somerset \| Sullivan \| Susquehanna \| Tioga \| Union \| Venango \| Warren \| Washington \| Wayne \| Westmoreland \| Wyoming \| York

Regions of Maryland
Western \| Southern \| Eastern Shore \| Baltimore-Washington Metro Area \| Chesapeake \|
Largest Cities
Annapolis \| Baltimore \| Bowie \| College Park \| Columbia \| Cumberland \| Frederick \| Gaithersburg \| Greenbelt \| Hagerstown \| Rockville \| Salisbury \| Suitland \| Takoma Park \| Towson \| Waldorf \| Westminster \| Wheaton \| White Oak \| Woodlawn
Counties
Allegany \| Anne Arundel \| Baltimore City \| Baltimore County \| Calvert \| Caroline \| Carroll \| Cecil \| Charles \| Dorchester \| Frederick \| Garrett \| Harford \| Howard \| Kent \| Montgomery \| Prince George's \| Queen Anne's \| St. Mary's \| Somerset \| Talbot \| Washington \| Wicomico \| Worcester

Regions of Pennsylvania
Piedmont \| South Mountains \| Ridge-and-valley Appalachians \| Allegheny Plateau
Delaware Valley (Philadelphia metropolitan area) \| Northern Tier \| New York metropolitan area
Largest Cities
Allentown \| Altoona \| Bethel Park \| Bethlehem \| Chester \| Drexel Hill \| Erie \| Harrisburg \| Lancaster \| Levittown \| Mount Lebanon \| New Cumberland \| Norristown \| Penn Hills \| Philadelphia \| Pittsburgh \| Reading \| Scranton \| State College \| Wilkes-Barre
Counties
Adams \| Allegheny \| Armstrong \| Beaver \| Bedford \| Berks \| Blair \| Bradford \| Bucks \| Butler \| Cambria \| Cameron \| Carbon \| Centre \| Chester \| Clarion \| Clearfield \| Clinton \| Columbia \| Crawford \| Cumberland \| Dauphin \| Delaware \| Elk \| Erie \| Fayette \| Forest \| Franklin \| Fulton \| Greene \| Huntingdon \| Indiana \| Jefferson \| Juniata \| Lackawanna \| Lancaster \| Lawrence \| Lebanon \| Lehigh \| Luzerne \| Lycoming \| McKean \| Mercer \| Mifflin \| Monroe \| Montgomery \| Montour \| Northampton \| Northumberland \| Perry \| Philadelphia \| Potter \| Schuylkill \| Snyder \| Somerset \| Sullivan \| Susquehanna \| Tioga \| Union \| Venango \| Warren \| Washington \| Wayne \| Westmoreland \| Wyoming \| York