| Piqua to Orbetello | 4,668.97 mi (7,513.98 km) |
| Piqua to Oria | 5,015.77 mi (8,072.10 km) |
| Piqua to Oristano | 4,655.37 mi (7,492.10 km) |
| Piqua to Orta Nova | 4,901.30 mi (7,887.88 km) |
| Piqua to Orte | 4,717.22 mi (7,591.63 km) |
| Piqua to Ortona | 4,805.09 mi (7,733.04 km) |
| Piqua to Orvieto | 4,695.49 mi (7,556.66 km) |
| Piqua to Orzinuovi | 4,502.41 mi (7,245.93 km) |
| Piqua to Osimo | 4,721.64 mi (7,598.75 km) |
| Piqua to Ospitaletto | 4,502.29 mi (7,245.73 km) |
| Piqua to Ostuni | 5,003.71 mi (8,052.70 km) |
| Piqua to Ottaviano | 4,869.93 mi (7,837.40 km) |
| Piqua to Ovada | 4,477.87 mi (7,206.44 km) |
| Piqua to Ozieri | 4,646.97 mi (7,478.58 km) |
| Piqua to Paceco | 4,905.67 mi (7,894.91 km) |
