| Castano Primo to Octeville | 560.23 mi (901.60 km) |
| Castano Primo to Oignies | 431.85 mi (694.99 km) |
| Castano Primo to Oissel | 443.79 mi (714.21 km) |
| Castano Primo to Olivet | 362.29 mi (583.06 km) |
| Castano Primo to Ollioules | 220.32 mi (354.57 km) |
| Castano Primo to Olonne-sur-Mer | 509.64 mi (820.19 km) |
| Castano Primo to Oloron-Sainte-Marie | 490.36 mi (789.17 km) |
| Castano Primo to Onet Village | 312.62 mi (503.12 km) |
| Castano Primo to Onnaing | 410.75 mi (661.04 km) |
| Castano Primo to Orange | 216.97 mi (349.18 km) |
| Castano Primo to Orchies | 425.11 mi (684.15 km) |
| Castano Primo to Orleans | 363.02 mi (584.22 km) |
| Castano Primo to Orly | 371.83 mi (598.40 km) |
| Castano Primo to Ormesson-sur-Marne | 368.01 mi (592.26 km) |
| Castano Primo to Orsay | 377.91 mi (608.18 km) |
