| Caerphilly to Octeville | 151.46 mi (243.75 km) |
| Caerphilly to Oignies | 280.52 mi (451.45 km) |
| Caerphilly to Oissel | 244.47 mi (393.44 km) |
| Caerphilly to Olivet | 343.54 mi (552.87 km) |
| Caerphilly to Ollioules | 719.91 mi (1,158.59 km) |
| Caerphilly to Olonne-sur-Mer | 354.43 mi (570.41 km) |
| Caerphilly to Oloron-Sainte-Marie | 591.90 mi (952.57 km) |
| Caerphilly to Onet Village | 565.79 mi (910.55 km) |
| Caerphilly to Onnaing | 307.55 mi (494.95 km) |
| Caerphilly to Orange | 633.80 mi (1,020.00 km) |
| Caerphilly to Orchies | 290.88 mi (468.13 km) |
| Caerphilly to Orleans | 341.74 mi (549.98 km) |
| Caerphilly to Orly | 316.11 mi (508.74 km) |
| Caerphilly to Ormesson-sur-Marne | 319.35 mi (513.94 km) |
| Caerphilly to Orsay | 311.14 mi (500.73 km) |
