| Merzenich to Obernburg am Main | 133.93 mi (215.55 km) |
| Merzenich to Obernkirchen | 149.31 mi (240.28 km) |
| Merzenich to Oberschleissheim | 287.55 mi (462.77 km) |
| Merzenich to Oberstdorf | 290.64 mi (467.74 km) |
| Merzenich to Obertraubling | 281.93 mi (453.72 km) |
| Merzenich to Obertshausen | 114.24 mi (183.86 km) |
| Merzenich to Oberursel | 99.82 mi (160.65 km) |
| Merzenich to Ochsenfurt | 176.26 mi (283.67 km) |
| Merzenich to Ochsenhausen | 244.54 mi (393.55 km) |
| Merzenich to Ochtrup | 99.49 mi (160.11 km) |
| Merzenich to Odenthal | 29.41 mi (47.33 km) |
| Merzenich to Oelde | 98.75 mi (158.93 km) |
| Merzenich to Oelsnitz | 248.78 mi (400.38 km) |
| Merzenich to Oer-Erkenschwick | 64.50 mi (103.80 km) |
| Merzenich to Oerlinghausen | 121.32 mi (195.24 km) |
