| Quattro Castella to Orbetello | 156.12 mi (251.25 km) |
| Quattro Castella to Oria | 462.89 mi (744.95 km) |
| Quattro Castella to Oristano | 340.39 mi (547.80 km) |
| Quattro Castella to Orta Nova | 349.65 mi (562.70 km) |
| Quattro Castella to Orte | 178.26 mi (286.88 km) |
| Quattro Castella to Ortona | 252.46 mi (406.29 km) |
| Quattro Castella to Orvieto | 155.73 mi (250.62 km) |
| Quattro Castella to Orzinuovi | 59.03 mi (95.00 km) |
| Quattro Castella to Osimo | 169.54 mi (272.84 km) |
| Quattro Castella to Ospitaletto | 66.53 mi (107.07 km) |
| Quattro Castella to Ostuni | 450.56 mi (725.11 km) |
| Quattro Castella to Ottaviano | 331.20 mi (533.01 km) |
| Quattro Castella to Ovada | 89.50 mi (144.03 km) |
| Quattro Castella to Ozieri | 289.43 mi (465.80 km) |
| Quattro Castella to Paceco | 471.97 mi (759.57 km) |
