| Name of the place | CERL ID of a place | Country | Longitude | Latitude | |
|---|---|---|---|---|---|
| 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 | — | — | |
| Mayenne (Mayenne) | cnl00003124 | France | -0.6183 | 48.312 | |
| Mayland | cnl00021430 | England | 0.766944444444444 | 51.6802777777778 | |
| Maynooth | cnl00018594 | Ireland | -6.58305555555556 | 53.3830555555556 | |
| Meaux | cnl00011611 | — | 2.87 | 48.95 | |
| Mecca | cnl00001781 | Saudi Arabia | 39.8333333333333 | 21.4166666666667 | |
| Mechelen | cnl00011474 | Belgium | 4.47 | 51.03 | |
| Medellín | cnl00019655 | Colombia | — | — | |
| Medemblik | cnl00003120 | Netherlands | 5.03305555555556 | 52.6830555555556 | |
| Medina de Rioseco | cnl00003542 | Spain | -5.04916666666667 | 41.8830555555556 | |
| Medina del Campo | cnl00000946 | Spain | -4.91666666666667 | 41.2997222222222 |