| Llantwit Major to Mangualde | 773.82 mi (1,245.35 km) |
| Llantwit Major to Marco de Canavezes | 740.36 mi (1,191.50 km) |
| Llantwit Major to Marinha Grande | 846.92 mi (1,362.98 km) |
| Llantwit Major to Massama | 917.92 mi (1,477.25 km) |
| Llantwit Major to Matosinhos | 748.60 mi (1,204.75 km) |
| Llantwit Major to Mealhada | 797.82 mi (1,283.97 km) |
| Llantwit Major to Melgaco | 680.36 mi (1,094.93 km) |
| Llantwit Major to Melres | 751.73 mi (1,209.78 km) |
| Llantwit Major to Mira | 798.64 mi (1,285.29 km) |
| Llantwit Major to Miranda do Corvo | 815.07 mi (1,311.73 km) |
| Llantwit Major to Mirandela | 707.58 mi (1,138.73 km) |
| Llantwit Major to Mogadouro | 712.73 mi (1,147.04 km) |
| Llantwit Major to Moimenta da Beira | 746.79 mi (1,201.84 km) |
| Llantwit Major to Moita | 920.83 mi (1,481.94 km) |
| Llantwit Major to Moncao | 686.60 mi (1,104.98 km) |
