| Harlow to Mangualde | 858.18 mi (1,381.11 km) |
| Harlow to Marco de Canavezes | 830.07 mi (1,335.87 km) |
| Harlow to Marinha Grande | 937.23 mi (1,508.32 km) |
| Harlow to Massama | 1,007.33 mi (1,621.14 km) |
| Harlow to Matosinhos | 842.62 mi (1,356.06 km) |
| Harlow to Mealhada | 886.81 mi (1,427.18 km) |
| Harlow to Melgaco | 775.03 mi (1,247.29 km) |
| Harlow to Melres | 842.95 mi (1,356.59 km) |
| Harlow to Mira | 889.96 mi (1,432.25 km) |
| Harlow to Miranda do Corvo | 902.15 mi (1,451.87 km) |
| Harlow to Mirandela | 790.33 mi (1,271.91 km) |
| Harlow to Mogadouro | 790.76 mi (1,272.61 km) |
| Harlow to Moimenta da Beira | 831.31 mi (1,337.86 km) |
| Harlow to Moita | 1,007.89 mi (1,622.05 km) |
| Harlow to Moncao | 782.80 mi (1,259.79 km) |
