| Walker Mill to Orbetello | 4,403.31 mi (7,086.44 km) |
| Walker Mill to Oria | 4,756.37 mi (7,654.64 km) |
| Walker Mill to Oristano | 4,371.75 mi (7,035.64 km) |
| Walker Mill to Orta Nova | 4,640.96 mi (7,468.90 km) |
| Walker Mill to Orte | 4,454.35 mi (7,168.58 km) |
| Walker Mill to Ortona | 4,546.42 mi (7,316.76 km) |
| Walker Mill to Orvieto | 4,433.25 mi (7,134.63 km) |
| Walker Mill to Orzinuovi | 4,248.93 mi (6,837.99 km) |
| Walker Mill to Osimo | 4,466.35 mi (7,187.90 km) |
| Walker Mill to Ospitaletto | 4,249.92 mi (6,839.59 km) |
| Walker Mill to Ostuni | 4,745.26 mi (7,636.76 km) |
| Walker Mill to Ottaviano | 4,604.33 mi (7,409.96 km) |
| Walker Mill to Ovada | 4,217.65 mi (6,787.65 km) |
| Walker Mill to Ozieri | 4,367.44 mi (7,028.71 km) |
| Walker Mill to Paceco | 4,622.45 mi (7,439.11 km) |
