Washington County, Maryland

Washington County
Burnside's Bridge in Washington County, site of heavy combat during the Battle of Antietam
Location within the U.S. state of Maryland
Maryland's location within the U.S.
Coordinates: 39°36′N 77°49′W / 39.6°N 77.81°W / 39.6; -77.81
Country United States
State Maryland
FoundedSeptember 6, 1776
Named afterGeorge Washington
SeatHagerstown
Largest cityHagerstown
Area
  Total
467 sq mi (1,210 km2)
  Land458 sq mi (1,190 km2)
  Water9.6 sq mi (25 km2)  2.0%
Population
 (2020)
  Total
154,705
  Estimate 
(2023)
155,813
  Density330/sq mi (130/km2)
Time zoneUTC−5 (Eastern)
  Summer (DST)UTC−4 (EDT)
Congressional district6th
Websitewww.washco-md.net

Washington County is a county located in the U.S. state of Maryland. The population was 154,705 as of the 2020 census. Its county seat and largest city is Hagerstown. The county is part of the Western Maryland region of the state.

Washington County was the first county in the United States to be named for the Revolutionary War general (and later President) George Washington. Washington County is one of three Maryland counties recognized by the Appalachian Regional Commission as being part of Appalachia. The county borders southern Pennsylvania to the north, Northern Virginia to the south, and the Martinsburg Panhandle of West Virginia to the south and west. Washington County is included in the Hagerstown-Martinsburg, MD-WV Metropolitan Statistical Area, which is also included in the Washington-Baltimore-Arlington, DC-MD-VA-WV-PA Combined Statistical Area.