| Maidenhead to Mangualde | 825.53 mi (1,328.56 km) |
| Maidenhead to Marco de Canavezes | 796.44 mi (1,281.74 km) |
| Maidenhead to Marinha Grande | 903.68 mi (1,454.32 km) |
| Maidenhead to Massama | 974.03 mi (1,567.55 km) |
| Maidenhead to Matosinhos | 808.29 mi (1,300.82 km) |
| Maidenhead to Mealhada | 853.40 mi (1,373.42 km) |
| Maidenhead to Melgaco | 740.47 mi (1,191.68 km) |
| Maidenhead to Melres | 809.09 mi (1,302.10 km) |
| Maidenhead to Mira | 856.16 mi (1,377.86 km) |
| Maidenhead to Miranda do Corvo | 869.10 mi (1,398.68 km) |
| Maidenhead to Mirandela | 757.81 mi (1,219.57 km) |
| Maidenhead to Mogadouro | 759.08 mi (1,221.62 km) |
| Maidenhead to Moimenta da Beira | 798.57 mi (1,285.17 km) |
| Maidenhead to Moita | 975.00 mi (1,569.12 km) |
| Maidenhead to Moncao | 748.01 mi (1,203.81 km) |
