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
Washington, DC Metropolitan Area Special Flight Rules Area Within the ADIZ is an even more sensitive zone designated the "Washington, D.C. Metropolitan Area Flight Restricted Zone" (DC FRZ). The DC FRZ extends approximately around the DCA VOR/DME. Flight within the FRZ is restricted to governmental, certain scheduled commercial and a limited set of waivered flights. Three general aviation airports (known as the "Maryland 3" or the "DC 3") are located inside the DC FRZ: College Park Airport (CGS), Washington Executive/Hyde Field (W32), and Potomac Airport (VKX). Pilots' groups, led by the Aircraft Owners and Pilots Association (AOPA), have argued that the ADIZ is unnecessary and has a harmful