| Harrow Weald to Mangualde | 838.03 mi (1,348.69 km) |
| Harrow Weald to Marco de Canavezes | 809.44 mi (1,302.66 km) |
| Harrow Weald to Marinha Grande | 916.64 mi (1,475.19 km) |
| Harrow Weald to Massama | 986.87 mi (1,588.22 km) |
| Harrow Weald to Matosinhos | 821.65 mi (1,322.32 km) |
| Harrow Weald to Mealhada | 866.29 mi (1,394.16 km) |
| Harrow Weald to Melgaco | 753.95 mi (1,213.36 km) |
| Harrow Weald to Melres | 822.21 mi (1,323.21 km) |
| Harrow Weald to Mira | 869.25 mi (1,398.92 km) |
| Harrow Weald to Miranda do Corvo | 881.81 mi (1,419.13 km) |
| Harrow Weald to Mirandela | 770.24 mi (1,239.58 km) |
| Harrow Weald to Mogadouro | 771.09 mi (1,240.95 km) |
| Harrow Weald to Moimenta da Beira | 811.12 mi (1,305.37 km) |
| Harrow Weald to Moita | 987.64 mi (1,589.45 km) |
| Harrow Weald to Moncao | 761.60 mi (1,225.68 km) |
