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
Maryland Maryland, with large communities existing in the suburbs of Washington, D.C. (particularly Montgomery County and Prince George's County) and the city of Baltimore. The Greater Washington area has the largest population of Ethiopians outside of Africa. The Ethiopian community of Greater DC was historically based in Washington D.C.'s Adams Morgan and Shaw neighborhoods, but as the community has grown, many Ethiopians have settled in Silver Spring. The Washington, D.C. metropolitan area is also home to large Eritrean and Somali communities. The top reported ancestries by Maryland residents are: German (15%), Irish (11%), English (8%), American (7%), Italian (6%), and Polish