| Rock Island to Mangualde | 4,136.06 mi (6,656.35 km) |
| Rock Island to Marco de Canavezes | 4,098.26 mi (6,595.50 km) |
| Rock Island to Marinha Grande | 4,112.97 mi (6,619.19 km) |
| Rock Island to Massama | 4,132.47 mi (6,650.57 km) |
| Rock Island to Matosinhos | 4,073.52 mi (6,555.70 km) |
| Rock Island to Mealhada | 4,112.69 mi (6,618.74 km) |
| Rock Island to Melgaco | 4,060.79 mi (6,535.22 km) |
| Rock Island to Melres | 4,091.07 mi (6,583.94 km) |
| Rock Island to Mira | 4,098.10 mi (6,595.25 km) |
| Rock Island to Miranda do Corvo | 4,127.96 mi (6,643.32 km) |
| Rock Island to Mirandela | 4,131.03 mi (6,648.24 km) |
| Rock Island to Mogadouro | 4,157.11 mi (6,690.22 km) |
| Rock Island to Moimenta da Beira | 4,129.47 mi (6,645.74 km) |
| Rock Island to Moita | 4,149.74 mi (6,678.36 km) |
| Rock Island to Moncao | 4,052.78 mi (6,522.32 km) |
