| Sion to Mangualde | 851.09 mi (1,369.70 km) |
| Sion to Marco de Canavezes | 848.02 mi (1,364.76 km) |
| Sion to Marinha Grande | 935.16 mi (1,504.99 km) |
| Sion to Massama | 989.80 mi (1,592.94 km) |
| Sion to Matosinhos | 872.98 mi (1,404.93 km) |
| Sion to Mealhada | 889.86 mi (1,432.08 km) |
| Sion to Melgaco | 823.57 mi (1,325.41 km) |
| Sion to Melres | 863.31 mi (1,389.37 km) |
| Sion to Mira | 900.67 mi (1,449.48 km) |
| Sion to Miranda do Corvo | 895.29 mi (1,440.84 km) |
| Sion to Mirandela | 794.01 mi (1,277.83 km) |
| Sion to Mogadouro | 778.35 mi (1,252.64 km) |
| Sion to Moimenta da Beira | 830.94 mi (1,337.27 km) |
| Sion to Moita | 981.73 mi (1,579.95 km) |
| Sion to Moncao | 834.73 mi (1,343.37 km) |
