| Shoreline to Mangualde | 5,138.24 mi (8,269.20 km) |
| Shoreline to Marco de Canavezes | 5,094.46 mi (8,198.74 km) |
| Shoreline to Marinha Grande | 5,144.25 mi (8,278.87 km) |
| Shoreline to Massama | 5,185.26 mi (8,344.87 km) |
| Shoreline to Matosinhos | 5,076.14 mi (8,169.25 km) |
| Shoreline to Mealhada | 5,126.96 mi (8,251.04 km) |
| Shoreline to Melgaco | 5,041.07 mi (8,112.81 km) |
| Shoreline to Melres | 5,092.33 mi (8,195.31 km) |
| Shoreline to Mira | 5,114.77 mi (8,231.42 km) |
| Shoreline to Miranda do Corvo | 5,145.96 mi (8,281.62 km) |
| Shoreline to Mirandela | 5,110.30 mi (8,224.24 km) |
| Shoreline to Mogadouro | 5,133.66 mi (8,261.83 km) |
| Shoreline to Moimenta da Beira | 5,123.09 mi (8,244.82 km) |
| Shoreline to Moita | 5,200.98 mi (8,370.18 km) |
| Shoreline to Moncao | 5,036.34 mi (8,105.20 km) |
