| Fort Thomas to Orbetello | 4,722.84 mi (7,600.68 km) |
| Fort Thomas to Oria | 5,070.85 mi (8,160.74 km) |
| Fort Thomas to Oristano | 4,706.02 mi (7,573.61 km) |
| Fort Thomas to Orta Nova | 4,956.17 mi (7,976.19 km) |
| Fort Thomas to Orte | 4,771.59 mi (7,679.12 km) |
| Fort Thomas to Ortona | 4,860.19 mi (7,821.72 km) |
| Fort Thomas to Orvieto | 4,749.95 mi (7,644.31 km) |
| Fort Thomas to Orzinuovi | 4,558.19 mi (7,335.70 km) |
| Fort Thomas to Osimo | 4,777.25 mi (7,688.23 km) |
| Fort Thomas to Ospitaletto | 4,558.24 mi (7,335.78 km) |
| Fort Thomas to Ostuni | 5,058.94 mi (8,141.58 km) |
| Fort Thomas to Ottaviano | 4,923.91 mi (7,924.27 km) |
| Fort Thomas to Ovada | 4,532.56 mi (7,294.45 km) |
| Fort Thomas to Ozieri | 4,698.38 mi (7,561.32 km) |
| Fort Thomas to Paceco | 4,956.51 mi (7,976.73 km) |
