| Thornbury to Mangualde | 800.16 mi (1,287.74 km) |
| Thornbury to Marco de Canavezes | 768.05 mi (1,236.06 km) |
| Thornbury to Marinha Grande | 875.02 mi (1,408.20 km) |
| Thornbury to Massama | 945.91 mi (1,522.30 km) |
| Thornbury to Matosinhos | 777.46 mi (1,251.20 km) |
| Thornbury to Mealhada | 825.46 mi (1,328.45 km) |
| Thornbury to Melgaco | 709.21 mi (1,141.37 km) |
| Thornbury to Melres | 779.85 mi (1,255.04 km) |
| Thornbury to Mira | 826.90 mi (1,330.77 km) |
| Thornbury to Miranda do Corvo | 842.24 mi (1,355.46 km) |
| Thornbury to Mirandela | 733.29 mi (1,180.11 km) |
| Thornbury to Mogadouro | 737.18 mi (1,186.37 km) |
| Thornbury to Moimenta da Beira | 773.09 mi (1,244.17 km) |
| Thornbury to Moita | 948.21 mi (1,526.00 km) |
| Thornbury to Moncao | 715.88 mi (1,152.10 km) |
