| Prairie Ridge to Orbetello | 5,621.97 mi (9,047.69 km) |
| Prairie Ridge to Oria | 5,896.58 mi (9,489.63 km) |
| Prairie Ridge to Oristano | 5,703.00 mi (9,178.10 km) |
| Prairie Ridge to Orta Nova | 5,800.17 mi (9,334.48 km) |
| Prairie Ridge to Orte | 5,650.34 mi (9,093.35 km) |
| Prairie Ridge to Ortona | 5,706.43 mi (9,183.62 km) |
| Prairie Ridge to Orvieto | 5,627.92 mi (9,057.27 km) |
| Prairie Ridge to Orzinuovi | 5,413.43 mi (8,712.08 km) |
| Prairie Ridge to Osimo | 5,615.49 mi (9,037.26 km) |
| Prairie Ridge to Ospitaletto | 5,407.73 mi (8,702.89 km) |
| Prairie Ridge to Ostuni | 5,880.95 mi (9,464.48 km) |
| Prairie Ridge to Ottaviano | 5,799.75 mi (9,333.80 km) |
| Prairie Ridge to Ovada | 5,425.60 mi (8,731.66 km) |
| Prairie Ridge to Ozieri | 5,674.14 mi (9,131.64 km) |
| Prairie Ridge to Paceco | 5,924.69 mi (9,534.86 km) |
