| Castalla to Oberkirch | 813.31 mi (1,308.89 km) |
| Castalla to Obernburg am Main | 914.53 mi (1,471.79 km) |
| Castalla to Obernkirchen | 1,054.82 mi (1,697.57 km) |
| Castalla to Oberschleissheim | 904.44 mi (1,455.55 km) |
| Castalla to Oberstdorf | 821.16 mi (1,321.53 km) |
| Castalla to Obertraubling | 958.31 mi (1,542.25 km) |
| Castalla to Obertshausen | 919.56 mi (1,479.89 km) |
| Castalla to Oberursel | 921.15 mi (1,482.45 km) |
| Castalla to Ochsenfurt | 929.03 mi (1,495.13 km) |
| Castalla to Ochsenhausen | 843.00 mi (1,356.67 km) |
| Castalla to Ochtrup | 1,013.24 mi (1,630.65 km) |
| Castalla to Odenthal | 938.98 mi (1,511.14 km) |
| Castalla to Oelde | 1,008.58 mi (1,623.15 km) |
| Castalla to Oelsnitz | 1,029.93 mi (1,657.50 km) |
| Castalla to Oer-Erkenschwick | 979.23 mi (1,575.91 km) |
