Founded in 1654, Calvert County is one of 23 counties in the state of Maryland. Historically, Calvert County was formed from Patuxent County which was from unorganized territory. Renamed Calvert County in 1658. The city of Prince Frederick is the county seat. With FIPS code of 9, Calvert County has a population of 93,928 and area of 345 square miles (894 km2).
List of all cities in Calvert County, MD alphabetically
| City/Town | Postal Code | Area Code |
| Barstow, MD | 20610 | 410/443/667 |
| Broomes Island, MD | 20615 | 410/443/667 |
| Chesapeake Beach, MD | 20732 | 410/443/667 |
| Dares Beach, MD | 20678 | 410/443/667 |
| Dowell, MD | 20629 | 410/443/667 |
| Dunkirk, MD | 20754 | 410/443/667 |
| Holland Point, MD | 20714 | 410/443/667 |
| Huntingtown, MD | 20639 | 410/443/667 |
| Lusby, MD | 20657 | 410/443/667 |
| North Beach, MD | 20714 | 410/443/667 |
| Owings, MD | 20736 | 301/240/227 |
| Port Republic, MD | 20676 | 410/443/667 |
| Pr Frederick, MD | 20678 | 410/443/667 |
| Prince Frederick, MD | 20678 | 410/443/667 |
| Rose Haven, MD | 20714 | 410/443/667 |
| Saint Leonard, MD | 20685 | 410/443/667 |
| Solomons, MD | 20688 | 410/443/667 |
| Sunderland, MD | 20689 | 410/443/667 |