| Harpenden to Masanasa | 857.40 mi (1,379.84 km) |
| Harpenden to Masquefa | 719.90 mi (1,158.56 km) |
| Harpenden to Matadepera | 714.54 mi (1,149.93 km) |
| Harpenden to Mazarron | 983.56 mi (1,582.89 km) |
| Harpenden to Meco | 790.96 mi (1,272.92 km) |
| Harpenden to Medina del Campo | 757.97 mi (1,219.83 km) |
| Harpenden to Medina Sidonia | 1,095.12 mi (1,762.43 km) |
| Harpenden to Mejorada del Campo | 802.18 mi (1,290.99 km) |
| Harpenden to Meliana | 849.18 mi (1,366.62 km) |
| Harpenden to Mengibar | 971.44 mi (1,563.38 km) |
| Harpenden to Merida | 937.76 mi (1,509.18 km) |
| Harpenden to Miajadas | 917.25 mi (1,476.18 km) |
| Harpenden to Mieres | 643.27 mi (1,035.25 km) |
| Harpenden to Miguelturra | 904.61 mi (1,455.83 km) |
| Harpenden to Mijas | 1,072.11 mi (1,725.40 km) |
