| Viterbo to Marco de Canavezes | 1,044.22 mi (1,680.51 km) |
| Viterbo to Marinha Grande | 1,108.05 mi (1,783.24 km) |
| Viterbo to Massama | 1,146.63 mi (1,845.33 km) |
| Viterbo to Matosinhos | 1,072.25 mi (1,725.63 km) |
| Viterbo to Mealhada | 1,071.82 mi (1,724.93 km) |
| Viterbo to Melgaco | 1,039.27 mi (1,672.54 km) |
| Viterbo to Melres | 1,058.59 mi (1,703.64 km) |
| Viterbo to Mira | 1,085.43 mi (1,746.83 km) |
| Viterbo to Miranda do Corvo | 1,070.86 mi (1,723.39 km) |
| Viterbo to Mirandela | 990.97 mi (1,594.81 km) |
| Viterbo to Mogadouro | 969.17 mi (1,559.73 km) |
| Viterbo to Moimenta da Beira | 1,019.74 mi (1,641.12 km) |
| Viterbo to Moita | 1,134.34 mi (1,825.54 km) |
| Viterbo to Moncao | 1,050.52 mi (1,690.65 km) |
| Viterbo to Montalegre | 1,018.14 mi (1,638.53 km) |
