| Name of the place | CERL ID of a place | Country | Longitude | Latitude | |
|---|---|---|---|---|---|
| Marken | — | Netherlands | 5.106389 | 52.459444 | |
| Market Harborough | cnl00002575 | England | -0.9206 | 52.4775 | |
| Markneukirchen | cnl00030026 | — | — | — | |
| Marktredwitz | cnl00038893 | Germany | 12.0858333333333 | 50.0041666666667 | |
| Marlborough | cnl00011557 | England | -1.71972222222222 | 51.42 | |
| Marlborough (Wiltshire) | cnl00011557 | England | -1.72 | 51.42 | |
| Marly-le-Roy | cnl00021165 | France | — | — | |
| Marmande | cnl00011561 | France | 0.17 | 44.5 | |
| Marnes-la-Coquette | cnl00019881 | France | — | — | |
| Marostica | cnl00017756 | Italy | — | — | |
| Marrakech | cnl00019368 | Morocco | -7.973328 | 31.669746 | |
| Marseille | cnl00006410 | France | 5.4 | 43.3 | |
| Marston | cnl00023950 | England | — | — | |
| Marthon | cnl00021763 | France | 0.4453 | 45.6128 | |
| Martigues | cnl00017134 | France | — | — | |
| Martinique | cnl00025132 | France: DOM TOM | — | — | |
| Martres | cnl00026120 | France | 1.0117 | 43.1997 | |
| Marylebone (London) | cnl00017259 | England | -0.147 | 51.5177 | |
| Massachusetts | cnl00029320 | United States | — | — | |
| Mathieu | cnl00023537 | France | -0.3719 | 49.2558 | |
| Mauléon | cnl00019951 | France | -0.8858 | 43.2253 | |
| Mauriac | cnl00021730 | France | — | — | |
| Mauritius | cnl00020451 | — | — | — | |
| Mauves-sur-Huisne | cnl00021302 | — | — | — | |
| Mauvezin | cnl00019676 | France | — | — |