| Porterville to Orbetello | 6,171.55 mi (9,932.15 km) |
| Porterville to Oria | 6,475.02 mi (10,420.54 km) |
| Porterville to Oristano | 6,221.96 mi (10,013.28 km) |
| Porterville to Orta Nova | 6,370.95 mi (10,253.06 km) |
| Porterville to Orte | 6,207.00 mi (9,989.21 km) |
| Porterville to Ortona | 6,274.42 mi (10,097.71 km) |
| Porterville to Orvieto | 6,184.32 mi (9,952.70 km) |
| Porterville to Orzinuovi | 5,971.92 mi (9,610.87 km) |
| Porterville to Osimo | 6,183.85 mi (9,951.95 km) |
| Porterville to Ospitaletto | 5,967.84 mi (9,604.32 km) |
| Porterville to Ostuni | 6,460.17 mi (10,396.63 km) |
| Porterville to Ottaviano | 6,360.69 mi (10,236.55 km) |
| Porterville to Ovada | 5,972.57 mi (9,611.93 km) |
| Porterville to Ozieri | 6,199.71 mi (9,977.47 km) |
| Porterville to Paceco | 6,458.36 mi (10,393.72 km) |
