| Cologne to Obernburg am Main | 122.61 mi (197.31 km) |
| Cologne to Obernkirchen | 130.67 mi (210.29 km) |
| Cologne to Oberschleissheim | 277.67 mi (446.86 km) |
| Cologne to Oberstdorf | 286.21 mi (460.60 km) |
| Cologne to Obertraubling | 268.74 mi (432.50 km) |
| Cologne to Obertshausen | 102.17 mi (164.43 km) |
| Cologne to Oberursel | 87.43 mi (140.71 km) |
| Cologne to Ochsenfurt | 163.66 mi (263.39 km) |
| Cologne to Ochsenhausen | 239.17 mi (384.91 km) |
| Cologne to Ochtrup | 88.28 mi (142.08 km) |
| Cologne to Odenthal | 9.78 mi (15.74 km) |
| Cologne to Oelde | 80.65 mi (129.80 km) |
| Cologne to Oelsnitz | 231.04 mi (371.83 km) |
| Cologne to Oer-Erkenschwick | 50.44 mi (81.17 km) |
| Cologne to Oerlinghausen | 102.53 mi (165.01 km) |
