Counties in Maryland Montgomery County (Rockville) Prince Georges County (Upper Marlboro) Baltimore County (Towson) Anne Arundel County (Annapolis) Baltimore city (Baltimore) Howard County (Ellicott City) Frederick County (Frederick) Harford County (Bel Air) Carroll County (Westminster) Charles County (La Plata) Washington County (Hagerstown) Saint Marys County (Leonardtown) Cecil County (Elkton) Wicomico County (Salisbury) Calvert County (Prince Frederick) Allegany County (Cumberland) Worcester County (Snow Hill) Queen Annes County (Centreville) Talbot County (Easton) Caroline County (Denton) Dorchester County (Cambridge) Garrett County (Oakland) Somerset County (Princess Anne) Kent County (Chestertown)