| Castellana Grotte to Marco de Canavezes | 1,314.97 mi (2,116.24 km) |
| Castellana Grotte to Marinha Grande | 1,372.14 mi (2,208.25 km) |
| Castellana Grotte to Massama | 1,405.48 mi (2,261.90 km) |
| Castellana Grotte to Matosinhos | 1,343.32 mi (2,161.86 km) |
| Castellana Grotte to Mealhada | 1,338.83 mi (2,154.65 km) |
| Castellana Grotte to Melgaco | 1,314.01 mi (2,114.70 km) |
| Castellana Grotte to Melres | 1,328.94 mi (2,138.73 km) |
| Castellana Grotte to Mira | 1,352.93 mi (2,177.33 km) |
| Castellana Grotte to Miranda do Corvo | 1,336.26 mi (2,150.51 km) |
| Castellana Grotte to Mirandela | 1,262.60 mi (2,031.95 km) |
| Castellana Grotte to Mogadouro | 1,239.81 mi (1,995.29 km) |
| Castellana Grotte to Moimenta da Beira | 1,289.17 mi (2,074.71 km) |
| Castellana Grotte to Moita | 1,392.12 mi (2,240.40 km) |
| Castellana Grotte to Moncao | 1,325.17 mi (2,132.65 km) |
| Castellana Grotte to Montalegre | 1,291.54 mi (2,078.53 km) |
