| | | Frederick County | MD | 24021 | Frederick-Gaithersburg-Bethesda,
MD 23224 | Washington-Arlington-Alexandria,
DC-VA-MD-WV 47900 | Washington-Baltimore-Arlington,
DC-MD-VA-WV-PA 548 | Outlying | metro county (urban) | nonspecialized | https://maps.google.com/?q=FrederickCounty+Maryland |
| | | Garrett County | MD | 24023 | | | | | nonmetro county (rural) | recreation | https://maps.google.com/?q=GarrettCounty+MD |
| | | Harford County | MD | 24025 | | Baltimore-Columbia-Towson,
MD 12580 | Washington-Baltimore-Arlington,
DC-MD-VA-WV-PA 548 | Outlying | metro county (urban) | federal/state
government-dependent | https://maps.google.com/?q=HarfordCounty+MD |
| | | Howard County | MD | 24027 | | Baltimore-Columbia-Towson,
MD 12580 | Washington-Baltimore-Arlington,
DC-MD-VA-WV-PA 548 | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=HowardCounty+MD |
| | | Kent County | MD | 24029 | | | | | nonmetro county (rural) | recreation | https://maps.google.com/?q=KentCounty+MD |
| | | Montgomery County | MD | 24031 | Frederick-Gaithersburg-Bethesda,
MD 23224 | Washington-Arlington-Alexandria,
DC-VA-MD-WV 47900 | Washington-Baltimore-Arlington,
DC-MD-VA-WV-PA 548 | Central | metro county (urban) | federal/state
government-dependent | https://maps.google.com/?q=MontgomeryCounty+Maryland |
| | | Prince George's
County | MD | 24033 | Washington, DC-MD 47764 | Washington-Arlington-Alexandria,
DC-VA-MD-WV 47900 | Washington-Baltimore-Arlington,
DC-MD-VA-WV-PA 548 | Central | metro county (urban) | federal/state
government-dependent | https://maps.google.com/?q=PrinceGeorge'sCounty+MD |
| | | Queen Anne's County | MD | 24035 | | Baltimore-Columbia-Towson,
MD 12580 | Washington-Baltimore-Arlington,
DC-MD-VA-WV-PA 548 | Outlying | metro county (urban) | recreation | https://maps.google.com/?q=QueenAnne'sCounty+MD |
| | | Somerset County | MD | 24039 | | Salisbury, MD 41540 | Salisbury-Ocean Pines, MD 480 | Outlying | metro county (urban) | federal/state
government-dependent | https://maps.google.com/?q=SomersetCounty+MD |
| | | St. Mary's County | MD | 24037 | | Lexington Park, MD 30500 | Washington-Baltimore-Arlington,
DC-MD-VA-WV-PA 548 | Central | metro county (urban) | federal/state
government-dependent | https://maps.google.com/?q=St.Mary'sCounty+MD |
