| Forest Grove to Orbetello | 5,741.18 mi (9,239.53 km) |
| Forest Grove to Oria | 6,016.81 mi (9,683.13 km) |
| Forest Grove to Oristano | 5,820.93 mi (9,367.89 km) |
| Forest Grove to Orta Nova | 5,920.16 mi (9,527.58 km) |
| Forest Grove to Orte | 5,769.82 mi (9,285.63 km) |
| Forest Grove to Ortona | 5,826.31 mi (9,376.54 km) |
| Forest Grove to Orvieto | 5,747.38 mi (9,249.52 km) |
| Forest Grove to Orzinuovi | 5,532.90 mi (8,904.33 km) |
| Forest Grove to Osimo | 5,735.35 mi (9,230.16 km) |
| Forest Grove to Ospitaletto | 5,527.25 mi (8,895.24 km) |
| Forest Grove to Ostuni | 6,001.21 mi (9,658.01 km) |
| Forest Grove to Ottaviano | 5,919.43 mi (9,526.40 km) |
| Forest Grove to Ovada | 5,544.63 mi (8,923.22 km) |
| Forest Grove to Ozieri | 5,792.36 mi (9,321.90 km) |
| Forest Grove to Paceco | 6,043.37 mi (9,725.87 km) |
