| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Adams Chance | city | Maryland | United States | 39.58 | -76.88 | 830 | |
| Adams Heights | city | Maryland | United States | 39.54 | -76.18 | 249 | |
| Adamstown | city | Maryland | United States | 39.31 | -77.47 | 298 | |
| Adamstown Village | city | Maryland | United States | 39.32 | -77.51 | 324 | |
| Adelina | city | Maryland | United States | 38.48 | -76.62 | 98 | |
| Adelphi | city | Maryland | United States | 39.00 | -76.97 | 131 | |
| Adelphi Park | city | Maryland | United States | 38.99 | -76.97 | 98 | |
| Adil Meadows | city | Maryland | United States | 39.29 | -76.76 | 830 | |
| Admiral (historical) | city | Maryland | United States | 39.09 | -76.73 | 144 | |
| Admiral Heights | city | Maryland | United States | 38.98 | -76.52 | 49 | |
| Admirals Walk | city | Maryland | United States | 39.03 | -76.45 | 19 | |
| Advocate Hill Farms | city | Maryland | United States | 39.60 | -76.46 | 830 | |
| Advocates Choice | city | Maryland | United States | 39.64 | -76.98 | 830 | |
| Ady | city | Maryland | United States | 39.64 | -76.33 | 400 | |
| Ady Estates | city | Maryland | United States | 39.67 | -76.35 | 354 |