| Caerfyrddin to Oberkirch | 593.60 mi (955.31 km) |
| Caerfyrddin to Obernburg am Main | 602.41 mi (969.49 km) |
| Caerfyrddin to Obernkirchen | 570.55 mi (918.21 km) |
| Caerfyrddin to Oberschleissheim | 745.53 mi (1,199.82 km) |
| Caerfyrddin to Oberstdorf | 720.09 mi (1,158.87 km) |
| Caerfyrddin to Obertraubling | 750.90 mi (1,208.46 km) |
| Caerfyrddin to Obertshausen | 584.57 mi (940.77 km) |
| Caerfyrddin to Oberursel | 570.96 mi (918.87 km) |
| Caerfyrddin to Ochsenfurt | 645.75 mi (1,039.23 km) |
| Caerfyrddin to Ochsenhausen | 684.32 mi (1,101.30 km) |
| Caerfyrddin to Ochtrup | 489.20 mi (787.29 km) |
| Caerfyrddin to Odenthal | 495.09 mi (796.76 km) |
| Caerfyrddin to Oelde | 531.47 mi (855.32 km) |
| Caerfyrddin to Oelsnitz | 719.89 mi (1,158.55 km) |
| Caerfyrddin to Oer-Erkenschwick | 494.48 mi (795.79 km) |
