| Horley to Mangualde | 815.39 mi (1,312.25 km) |
| Horley to Marco de Canavezes | 787.71 mi (1,267.69 km) |
| Horley to Marinha Grande | 894.80 mi (1,440.04 km) |
| Horley to Massama | 964.77 mi (1,552.65 km) |
| Horley to Matosinhos | 800.62 mi (1,288.48 km) |
| Horley to Mealhada | 844.32 mi (1,358.81 km) |
| Horley to Melgaco | 733.20 mi (1,179.97 km) |
| Horley to Melres | 800.70 mi (1,288.60 km) |
| Horley to Mira | 847.66 mi (1,364.18 km) |
| Horley to Miranda do Corvo | 859.51 mi (1,383.24 km) |
| Horley to Mirandela | 747.50 mi (1,202.98 km) |
| Horley to Mogadouro | 747.65 mi (1,203.23 km) |
| Horley to Moimenta da Beira | 788.55 mi (1,269.06 km) |
| Horley to Moita | 965.16 mi (1,553.28 km) |
| Horley to Moncao | 741.10 mi (1,192.69 km) |
