| Castel San Giorgio to Oria | 155.02 mi (249.48 km) |
| Castel San Giorgio to Oristano | 327.26 mi (526.68 km) |
| Castel San Giorgio to Orta Nova | 64.87 mi (104.39 km) |
| Castel San Giorgio to Orte | 166.45 mi (267.87 km) |
| Castel San Giorgio to Ortona | 109.35 mi (175.99 km) |
| Castel San Giorgio to Orvieto | 188.91 mi (304.02 km) |
| Castel San Giorgio to Orzinuovi | 399.33 mi (642.66 km) |
| Castel San Giorgio to Osimo | 196.69 mi (316.54 km) |
| Castel San Giorgio to Ospitaletto | 403.66 mi (649.63 km) |
| Castel San Giorgio to Ostuni | 150.93 mi (242.90 km) |
| Castel San Giorgio to Ottaviano | 12.51 mi (20.14 km) |
| Castel San Giorgio to Ovada | 406.53 mi (654.24 km) |
| Castel San Giorgio to Ozieri | 298.74 mi (480.77 km) |
| Castel San Giorgio to Paceco | 224.95 mi (362.02 km) |
| Castel San Giorgio to Pachino | 281.80 mi (453.51 km) |
