| Frederick to Orbetello | 4,404.69 mi (7,088.66 km) |
| Frederick to Oria | 4,756.91 mi (7,655.51 km) |
| Frederick to Oristano | 4,376.09 mi (7,042.63 km) |
| Frederick to Orta Nova | 4,641.60 mi (7,469.94 km) |
| Frederick to Orte | 4,455.31 mi (7,170.12 km) |
| Frederick to Ortona | 4,546.75 mi (7,317.29 km) |
| Frederick to Orvieto | 4,434.10 mi (7,135.99 km) |
| Frederick to Orzinuovi | 4,248.30 mi (6,836.98 km) |
| Frederick to Osimo | 4,466.12 mi (7,187.52 km) |
| Frederick to Ospitaletto | 4,249.12 mi (6,838.30 km) |
| Frederick to Ostuni | 4,745.65 mi (7,637.39 km) |
| Frederick to Ottaviano | 4,605.80 mi (7,412.32 km) |
| Frederick to Ovada | 4,218.07 mi (6,788.32 km) |
| Frederick to Ozieri | 4,371.09 mi (7,034.58 km) |
| Frederick to Paceco | 4,626.83 mi (7,446.16 km) |
