| Harpenden to Mombris | 431.36 mi (694.20 km) |
| Harpenden to Monchengladbach | 294.80 mi (474.43 km) |
| Harpenden to Monschau | 298.97 mi (481.14 km) |
| Harpenden to Montabaur | 367.00 mi (590.62 km) |
| Harpenden to Moosburg | 590.29 mi (949.98 km) |
| Harpenden to Morbach | 353.93 mi (569.60 km) |
| Harpenden to Morfelden-Walldorf | 408.74 mi (657.81 km) |
| Harpenden to Morlenbach | 425.86 mi (685.35 km) |
| Harpenden to Morsbach | 354.21 mi (570.05 km) |
| Harpenden to Mosbach | 449.77 mi (723.83 km) |
| Harpenden to Mosigkau | 536.79 mi (863.88 km) |
| Harpenden to Mossingen | 478.42 mi (769.94 km) |
| Harpenden to Much | 339.98 mi (547.15 km) |
| Harpenden to Mucheln | 522.63 mi (841.10 km) |
| Harpenden to Muhlacker | 450.39 mi (724.84 km) |
