| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Mackney | city | Ireland | 52.72 | -8.40 | 226 | 2216 | |
| Maigh Drithne | city | Ireland | 52.95 | -8.06 | 410 | 1207 | |
| Maigh Saotha | city | Ireland | 52.88 | -8.25 | 209 | 7070 | |
| Manseltown | city | Ireland | 52.70 | -7.72 | 403 | 1664 | |
| Mary Villa | city | Ireland | 52.83 | -8.44 | 252 | 3217 | |
| Mary Ville | city | Ireland | 52.83 | -8.44 | 252 | 3217 | |
| Moanavoggaun | city | Ireland | 53.02 | -8.20 | 187 | 1428 | |
| Moat Ville | city | Ireland | 53.05 | -8.05 | 262 | 1001 | |
| Modreeny | city | Ireland | 52.95 | -8.06 | 410 | 1207 | |
| Monanore | city | Ireland | 52.84 | -8.02 | 830 | 1317 | |
| Monroe Bridge | city | Ireland | 52.71 | -7.92 | 295 | 1910 | |
| Monsea | city | Ireland | 52.88 | -8.25 | 209 | 7070 | |
| Moycarky | city | Ireland | 52.63 | -7.81 | 830 | 8237 | |
| Moyne | city | Ireland | 52.73 | -7.71 | 410 | 1373 | |
| Mucklin | city | Ireland | 52.77 | -8.19 | 830 | 990 | |
| Mulgrave Bridge | city | Ireland | 52.66 | -7.95 | 255 | 1442 |