| Rock Island to Orbetello | 4,870.94 mi (7,839.02 km) |
| Rock Island to Oria | 5,210.04 mi (8,384.75 km) |
| Rock Island to Oristano | 4,873.66 mi (7,843.39 km) |
| Rock Island to Orta Nova | 5,097.10 mi (8,202.98 km) |
| Rock Island to Orte | 4,916.39 mi (7,912.16 km) |
| Rock Island to Ortona | 4,999.95 mi (8,046.64 km) |
| Rock Island to Orvieto | 4,894.23 mi (7,876.50 km) |
| Rock Island to Orzinuovi | 4,694.53 mi (7,555.12 km) |
| Rock Island to Osimo | 4,913.98 mi (7,908.29 km) |
| Rock Island to Ospitaletto | 4,693.41 mi (7,553.31 km) |
| Rock Island to Ostuni | 5,197.20 mi (8,364.08 km) |
| Rock Island to Ottaviano | 5,070.66 mi (8,160.45 km) |
| Rock Island to Ovada | 4,676.16 mi (7,525.55 km) |
| Rock Island to Ozieri | 4,861.59 mi (7,823.98 km) |
| Rock Island to Paceco | 5,122.25 mi (8,243.46 km) |
