| Rietberg to Marco de Canavezes | 1,072.54 mi (1,726.08 km) |
| Rietberg to Marinha Grande | 1,174.76 mi (1,890.60 km) |
| Rietberg to Massama | 1,239.90 mi (1,995.43 km) |
| Rietberg to Matosinhos | 1,091.54 mi (1,756.66 km) |
| Rietberg to Mealhada | 1,124.74 mi (1,810.10 km) |
| Rietberg to Melgaco | 1,029.05 mi (1,656.09 km) |
| Rietberg to Melres | 1,087.18 mi (1,749.64 km) |
| Rietberg to Mira | 1,131.70 mi (1,821.29 km) |
| Rietberg to Miranda do Corvo | 1,135.94 mi (1,828.12 km) |
| Rietberg to Mirandela | 1,023.86 mi (1,647.74 km) |
| Rietberg to Mogadouro | 1,016.38 mi (1,635.71 km) |
| Rietberg to Moimenta da Beira | 1,065.01 mi (1,713.97 km) |
| Rietberg to Moita | 1,236.24 mi (1,989.53 km) |
| Rietberg to Moncao | 1,038.79 mi (1,671.76 km) |
| Rietberg to Montalegre | 1,027.22 mi (1,653.16 km) |
