| Rietavas to Marco de Canavezes | 1,683.83 mi (2,709.87 km) |
| Rietavas to Marinha Grande | 1,784.76 mi (2,872.29 km) |
| Rietavas to Massama | 1,848.55 mi (2,974.95 km) |
| Rietavas to Matosinhos | 1,703.46 mi (2,741.45 km) |
| Rietavas to Mealhada | 1,735.11 mi (2,792.39 km) |
| Rietavas to Melgaco | 1,641.57 mi (2,641.85 km) |
| Rietavas to Melres | 1,698.61 mi (2,733.65 km) |
| Rietavas to Mira | 1,742.58 mi (2,804.42 km) |
| Rietavas to Miranda do Corvo | 1,745.56 mi (2,809.21 km) |
| Rietavas to Mirandela | 1,634.26 mi (2,630.09 km) |
| Rietavas to Mogadouro | 1,625.58 mi (2,616.12 km) |
| Rietavas to Moimenta da Beira | 1,675.14 mi (2,695.87 km) |
| Rietavas to Moita | 1,844.02 mi (2,967.66 km) |
| Rietavas to Moncao | 1,651.39 mi (2,657.66 km) |
| Rietavas to Montalegre | 1,639.03 mi (2,637.76 km) |
