| Cincinnati to Oerlinghausen | 4,278.07 mi (6,884.88 km) |
| Cincinnati to Oestrich-Winkel | 4,318.30 mi (6,949.63 km) |
| Cincinnati to Offenburg | 4,367.77 mi (7,029.24 km) |
| Cincinnati to Oftersheim | 4,362.44 mi (7,020.66 km) |
| Cincinnati to Ohrdruf | 4,394.33 mi (7,071.99 km) |
| Cincinnati to Ohringen | 4,404.04 mi (7,087.62 km) |
| Cincinnati to Olbernhau | 4,497.29 mi (7,237.70 km) |
| Cincinnati to Olching | 4,510.67 mi (7,259.22 km) |
| Cincinnati to Oldenburg | 4,222.86 mi (6,796.04 km) |
| Cincinnati to Oldenburg in Holstein | 4,280.93 mi (6,889.50 km) |
| Cincinnati to Olfen | 4,238.01 mi (6,820.41 km) |
| Cincinnati to Olpe | 4,278.00 mi (6,884.77 km) |
| Cincinnati to Olsberg | 4,291.64 mi (6,906.73 km) |
| Cincinnati to Oranienburg | 4,418.10 mi (7,110.24 km) |
| Cincinnati to Ortenberg | 4,346.94 mi (6,995.72 km) |
