| Castalla to Oerlinghausen | 1,027.32 mi (1,653.32 km) |
| Castalla to Oestrich-Winkel | 895.60 mi (1,441.34 km) |
| Castalla to Offenburg | 805.57 mi (1,296.44 km) |
| Castalla to Oftersheim | 873.65 mi (1,406.01 km) |
| Castalla to Ohrdruf | 1,011.19 mi (1,627.36 km) |
| Castalla to Ohringen | 888.84 mi (1,430.46 km) |
| Castalla to Olbernhau | 1,077.75 mi (1,734.48 km) |
| Castalla to Olching | 893.69 mi (1,438.26 km) |
| Castalla to Oldenburg | 1,090.25 mi (1,754.58 km) |
| Castalla to Oldenburg in Holstein | 1,212.85 mi (1,951.89 km) |
| Castalla to Olfen | 986.35 mi (1,587.38 km) |
| Castalla to Olpe | 952.54 mi (1,532.96 km) |
| Castalla to Olsberg | 986.48 mi (1,587.58 km) |
| Castalla to Oranienburg | 1,181.95 mi (1,902.17 km) |
| Castalla to Ortenberg | 941.61 mi (1,515.37 km) |
