Frederick County, Maryland Frederick County, Maryland Frederick County is located in the northern part of the U.S. state of Maryland. As of the 2010 U.S. Census, the population was 240,336. The county seat is Frederick. Frederick County is included in the Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area. Like other outlying sections of the Washington metropolitan area, Frederick County has experienced a rapid population increase in recent years. It borders the southern border of Pennsylvania and the northeastern border of Virginia. The county is home to Catoctin Mountain Park (encompassing the presidential retreat Camp David) and to the U.S. Army's Fort Detrick. It has also
History of Washington, D.C. east of Rock Creek Park. Large sections of the central city remained blighted for decades. By contrast, areas west of the Park, including virtually the entire portion of the District between the Georgetown and Chevy Chase neighborhoods (the latter of which spills into neighboring Chevy Chase, Maryland), contain some of the nation's most affluent and notable neighborhoods. During the early 20th century, the U Street Corridor served as an important center for African American culture in DC. The Washington Metro opened in 1976. A rising economy and gentrification in the late 1990s and early 2000s led to revitalization of many