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
Laurel, Maryland the poverty line, including 7.8% of those under age 18 and 6.4% of those age 65 or over. Laurel is traversed from north to south by U.S. Route 1 (US 1), which links Key West, Florida with the Canada–US border in Maine. On the west, the city is bordered by Interstate 95, and beyond the eastern border lies the Baltimore-Washington Parkway. Crossing all of these highways is the east-west artery of Maryland Route 198 (MD 198), which intersects with US 1 in the heart of Laurel. Other major state roads in Laurel are MD 216, which connects the city with