| Hemel Hempstead to Noventa Vicentina | 706.66 mi (1,137.26 km) |
| Hemel Hempstead to Novi di Modena | 703.86 mi (1,132.75 km) |
| Hemel Hempstead to Novi Ligure | 643.00 mi (1,034.80 km) |
| Hemel Hempstead to Nuoro | 917.61 mi (1,476.76 km) |
| Hemel Hempstead to Occhiobello | 725.76 mi (1,167.99 km) |
| Hemel Hempstead to Oderzo | 718.55 mi (1,156.40 km) |
| Hemel Hempstead to Oggiono | 607.37 mi (977.47 km) |
| Hemel Hempstead to Olbia | 885.16 mi (1,424.53 km) |
| Hemel Hempstead to Oleggio | 593.43 mi (955.04 km) |
| Hemel Hempstead to Olgiate Comasco | 594.73 mi (957.12 km) |
| Hemel Hempstead to Olgiate Olona | 599.69 mi (965.11 km) |
| Hemel Hempstead to Omegna | 571.79 mi (920.20 km) |
| Hemel Hempstead to Opera | 623.33 mi (1,003.15 km) |
| Hemel Hempstead to Oppeano | 693.59 mi (1,116.23 km) |
| Hemel Hempstead to Orbassano | 592.73 mi (953.90 km) |
