Washington County, Maryland 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. The closes states to Washington County is west Virginia, Pennsylvania, Virginia, and Tennessee. The western portions of the Province of Maryland (including present Washington County) were incorporated into Prince George's County in 1696. This original county included six current counties. The first to be created was Frederick, separated from Prince George's County in 1748. Following independence, the sovereign State of Maryland formed Washington County on September 6, 1776, by the division of Frederick County. At the same time, a portion
Frederick, Maryland and promoting the benefits of these systems. Frederick, Maryland Frederick is a city in, and the county seat of, Frederick County in the U.S. state of Maryland. It is part of the Baltimore–Washington Metropolitan Area. Frederick has long been an important crossroads, located at the intersection of a major north–south Indian trail and east–west routes to the Chesapeake Bay, both at Baltimore and what became Washington, D.C. and across the Appalachian mountains to the Ohio River watershed. It is a part of the Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area, which is part of a greater Washington-Baltimore-Arlington, DC-MD-VA-WV-PA Combined Statistical Area. The