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 City, Maryland the westernmost corner of Anne Arundel County. It is bordered by Laurel in Prince George's County to the west, by the CDP of Scaggsville in Howard County to the north, by the CDP of Jessup to the northeast, and by Fort Meade to the east. Uninhabited portions of Fort Meade are to the south. The Baltimore–Washington Parkway (Maryland Route 295) runs through the CDP, leading southwest to downtown Washington, D.C. and northeast to downtown Baltimore. Access from the parkway to Maryland City is via Maryland Route 198 (Fort Meade Road). Maryland Route 32 (the Patuxent Freeway) forms the northeast edge