| Prestwick to Orbetello | 1,147.25 mi (1,846.31 km) |
| Prestwick to Oria | 1,447.65 mi (2,329.77 km) |
| Prestwick to Oristano | 1,235.16 mi (1,987.80 km) |
| Prestwick to Orta Nova | 1,341.75 mi (2,159.34 km) |
| Prestwick to Orte | 1,179.11 mi (1,897.60 km) |
| Prestwick to Ortona | 1,245.00 mi (2,003.64 km) |
| Prestwick to Orvieto | 1,156.48 mi (1,861.17 km) |
| Prestwick to Orzinuovi | 942.97 mi (1,517.56 km) |
| Prestwick to Osimo | 1,154.59 mi (1,858.13 km) |
| Prestwick to Ospitaletto | 938.56 mi (1,510.47 km) |
| Prestwick to Ostuni | 1,433.20 mi (2,306.51 km) |
| Prestwick to Ottaviano | 1,331.84 mi (2,143.39 km) |
| Prestwick to Ovada | 949.81 mi (1,528.58 km) |
| Prestwick to Ozieri | 1,202.30 mi (1,934.91 km) |
| Prestwick to Paceco | 1,448.89 mi (2,331.77 km) |
