| Hoek van Holland to Orbetello | 737.53 mi (1,186.94 km) |
| Hoek van Holland to Oria | 1,019.20 mi (1,640.25 km) |
| Hoek van Holland to Oristano | 861.01 mi (1,385.67 km) |
| Hoek van Holland to Orta Nova | 915.91 mi (1,474.01 km) |
| Hoek van Holland to Orte | 762.36 mi (1,226.89 km) |
| Hoek van Holland to Ortona | 820.26 mi (1,320.08 km) |
| Hoek van Holland to Orvieto | 740.07 mi (1,191.02 km) |
| Hoek van Holland to Orzinuovi | 525.78 mi (846.16 km) |
| Hoek van Holland to Osimo | 729.31 mi (1,173.71 km) |
| Hoek van Holland to Ospitaletto | 519.61 mi (836.23 km) |
| Hoek van Holland to Ostuni | 1,004.45 mi (1,616.50 km) |
| Hoek van Holland to Ottaviano | 911.51 mi (1,466.94 km) |
| Hoek van Holland to Ovada | 547.85 mi (881.67 km) |
| Hoek van Holland to Ozieri | 820.61 mi (1,320.64 km) |
| Hoek van Holland to Paceco | 1,049.40 mi (1,688.85 km) |
