| Butte to Mangualde | 4,880.44 mi (7,854.30 km) |
| Butte to Marco de Canavezes | 4,837.94 mi (7,785.91 km) |
| Butte to Marinha Grande | 4,877.48 mi (7,849.54 km) |
| Butte to Massama | 4,912.29 mi (7,905.56 km) |
| Butte to Matosinhos | 4,817.39 mi (7,752.84 km) |
| Butte to Mealhada | 4,865.26 mi (7,829.87 km) |
| Butte to Melgaco | 4,788.76 mi (7,706.77 km) |
| Butte to Melres | 4,834.22 mi (7,779.92 km) |
| Butte to Mira | 4,852.16 mi (7,808.80 km) |
| Butte to Miranda do Corvo | 4,883.34 mi (7,858.97 km) |
| Butte to Mirandela | 4,859.24 mi (7,820.18 km) |
| Butte to Mogadouro | 4,883.75 mi (7,859.63 km) |
| Butte to Moimenta da Beira | 4,867.75 mi (7,833.88 km) |
| Butte to Moita | 4,928.68 mi (7,931.95 km) |
| Butte to Moncao | 4,782.96 mi (7,697.42 km) |
