| Castellammare del Golfo to Oria | 306.28 mi (492.91 km) |
| Castellammare del Golfo to Oristano | 264.44 mi (425.57 km) |
| Castellammare del Golfo to Orta Nova | 273.43 mi (440.05 km) |
| Castellammare del Golfo to Orte | 307.46 mi (494.81 km) |
| Castellammare del Golfo to Ortona | 309.29 mi (497.76 km) |
| Castellammare del Golfo to Orvieto | 326.70 mi (525.77 km) |
| Castellammare del Golfo to Orzinuovi | 531.56 mi (855.46 km) |
| Castellammare del Golfo to Osimo | 378.35 mi (608.89 km) |
| Castellammare del Golfo to Ospitaletto | 539.83 mi (868.77 km) |
| Castellammare del Golfo to Ostuni | 313.06 mi (503.82 km) |
| Castellammare del Golfo to Ottaviano | 212.88 mi (342.60 km) |
| Castellammare del Golfo to Ovada | 506.78 mi (815.59 km) |
| Castellammare del Golfo to Ozieri | 272.38 mi (438.35 km) |
| Castellammare del Golfo to Paceco | 18.24 mi (29.36 km) |
| Castellammare del Golfo to Pachino | 151.78 mi (244.27 km) |
