| Lake Butler to Mangualde | 4,160.43 mi (6,695.56 km) |
| Lake Butler to Marco de Canavezes | 4,131.51 mi (6,649.02 km) |
| Lake Butler to Marinha Grande | 4,113.91 mi (6,620.70 km) |
| Lake Butler to Massama | 4,112.20 mi (6,617.94 km) |
| Lake Butler to Matosinhos | 4,103.62 mi (6,604.13 km) |
| Lake Butler to Mealhada | 4,128.73 mi (6,644.56 km) |
| Lake Butler to Melgaco | 4,111.51 mi (6,616.84 km) |
| Lake Butler to Melres | 4,120.62 mi (6,631.50 km) |
| Lake Butler to Mira | 4,113.43 mi (6,619.93 km) |
| Lake Butler to Miranda do Corvo | 4,139.24 mi (6,661.46 km) |
| Lake Butler to Mirandela | 4,175.69 mi (6,720.12 km) |
| Lake Butler to Mogadouro | 4,201.57 mi (6,761.77 km) |
| Lake Butler to Moimenta da Beira | 4,161.91 mi (6,697.95 km) |
| Lake Butler to Moita | 4,129.22 mi (6,645.34 km) |
| Lake Butler to Moncao | 4,101.46 mi (6,600.67 km) |
