| Pikesville to Orbetello | 4,375.10 mi (7,041.05 km) |
| Pikesville to Oria | 4,727.76 mi (7,608.60 km) |
| Pikesville to Oristano | 4,345.07 mi (6,992.71 km) |
| Pikesville to Orta Nova | 4,612.40 mi (7,422.94 km) |
| Pikesville to Orte | 4,425.94 mi (7,122.86 km) |
| Pikesville to Ortona | 4,517.71 mi (7,270.55 km) |
| Pikesville to Orvieto | 4,404.78 mi (7,088.81 km) |
| Pikesville to Orzinuovi | 4,219.75 mi (6,791.03 km) |
| Pikesville to Osimo | 4,437.37 mi (7,141.25 km) |
| Pikesville to Ospitaletto | 4,220.66 mi (6,792.50 km) |
| Pikesville to Ostuni | 4,716.58 mi (7,590.60 km) |
| Pikesville to Ottaviano | 4,576.18 mi (7,364.64 km) |
| Pikesville to Ovada | 4,188.97 mi (6,741.49 km) |
| Pikesville to Ozieri | 4,340.39 mi (6,985.18 km) |
| Pikesville to Paceco | 4,595.79 mi (7,396.21 km) |
