| Heerhugowaard to Orbetello | 765.96 mi (1,232.70 km) |
| Heerhugowaard to Oria | 1,034.06 mi (1,664.16 km) |
| Heerhugowaard to Oristano | 899.45 mi (1,447.52 km) |
| Heerhugowaard to Orta Nova | 933.80 mi (1,502.80 km) |
| Heerhugowaard to Orte | 787.20 mi (1,266.88 km) |
| Heerhugowaard to Ortona | 839.49 mi (1,351.02 km) |
| Heerhugowaard to Orvieto | 765.24 mi (1,231.54 km) |
| Heerhugowaard to Orzinuovi | 552.34 mi (888.91 km) |
| Heerhugowaard to Osimo | 748.52 mi (1,204.63 km) |
| Heerhugowaard to Ospitaletto | 545.17 mi (877.36 km) |
| Heerhugowaard to Ostuni | 1,018.95 mi (1,639.84 km) |
| Heerhugowaard to Ottaviano | 933.53 mi (1,502.37 km) |
| Heerhugowaard to Ovada | 581.10 mi (935.19 km) |
| Heerhugowaard to Ozieri | 857.53 mi (1,380.06 km) |
| Heerhugowaard to Paceco | 1,080.06 mi (1,738.19 km) |
