| Swansea to Mangualde | 4,209.62 mi (6,774.73 km) |
| Swansea to Marco de Canavezes | 4,173.21 mi (6,716.13 km) |
| Swansea to Marinha Grande | 4,181.98 mi (6,730.25 km) |
| Swansea to Massama | 4,197.62 mi (6,755.41 km) |
| Swansea to Matosinhos | 4,147.72 mi (6,675.10 km) |
| Swansea to Mealhada | 4,184.53 mi (6,734.36 km) |
| Swansea to Melgaco | 4,138.73 mi (6,660.65 km) |
| Swansea to Melres | 4,165.29 mi (6,703.38 km) |
| Swansea to Mira | 4,169.70 mi (6,710.49 km) |
| Swansea to Miranda do Corvo | 4,199.02 mi (6,757.67 km) |
| Swansea to Mirandela | 4,208.32 mi (6,772.64 km) |
| Swansea to Mogadouro | 4,234.55 mi (6,814.84 km) |
| Swansea to Moimenta da Beira | 4,204.48 mi (6,766.46 km) |
| Swansea to Moita | 4,214.96 mi (6,783.33 km) |
| Swansea to Moncao | 4,130.29 mi (6,647.05 km) |
