| Ratingen to Oberkirch | 198.87 mi (320.05 km) |
| Ratingen to Obernburg am Main | 142.42 mi (229.20 km) |
| Ratingen to Obernkirchen | 117.70 mi (189.42 km) |
| Ratingen to Oberschleissheim | 297.71 mi (479.12 km) |
| Ratingen to Oberstdorf | 309.87 mi (498.68 km) |
| Ratingen to Obertraubling | 285.30 mi (459.15 km) |
| Ratingen to Obertshausen | 121.65 mi (195.77 km) |
| Ratingen to Oberursel | 106.95 mi (172.13 km) |
| Ratingen to Ochsenfurt | 181.64 mi (292.32 km) |
| Ratingen to Ochsenhausen | 262.47 mi (422.40 km) |
| Ratingen to Ochtrup | 64.24 mi (103.39 km) |
| Ratingen to Odenthal | 21.75 mi (35.00 km) |
| Ratingen to Oelde | 66.89 mi (107.66 km) |
| Ratingen to Oelsnitz | 239.72 mi (385.79 km) |
| Ratingen to Oer-Erkenschwick | 29.27 mi (47.10 km) |
