Manassas is an independent city in the Commonwealth of Virginia. As of the 2010 Census, the population was 37,821. The city borders Prince William County, the independent city of Manassas Park, and Fairfax County. The Bureau of Economic Analysis includes both Manassas and Manassas Park with Prince William County for statistical purposes.Manassas also serves as the seat of Prince William County. It surrounds the 38-acre county courthouse, but that county property is not part of the city. The City of Manassas has several important historic sites from the period 1850–1870.The City of Manassas is part of the Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area and it is situated in the Northern Virginia region.