Metro Washington Council of Governments
From The RadioReference Wiki
MW COG Metro Washington Council of Governments
Jurisdictional Pre-Fix Number
0 – Washington, DC 1 – Arlington County 2 – City of Alexandria 3 – Metro Washington Airport Authority 4 – Fairfax County 5 – Prince William County 6 – Loudoun County 7 – Montgomery County 8 – Prince George’s County 9 – Frederick County 10 - Charles