| Hertford to Octeville | 164.81 mi (265.24 km) |
| Hertford to Oignies | 161.66 mi (260.16 km) |
| Hertford to Oissel | 177.18 mi (285.15 km) |
| Hertford to Olivet | 285.64 mi (459.69 km) |
| Hertford to Ollioules | 658.52 mi (1,059.79 km) |
| Hertford to Olonne-sur-Mer | 371.42 mi (597.74 km) |
| Hertford to Oloron-Sainte-Marie | 594.88 mi (957.36 km) |
| Hertford to Onet Village | 527.93 mi (849.62 km) |
| Hertford to Onnaing | 186.82 mi (300.66 km) |
| Hertford to Orange | 575.09 mi (925.51 km) |
| Hertford to Orchies | 170.50 mi (274.40 km) |
| Hertford to Orleans | 283.21 mi (455.78 km) |
| Hertford to Orly | 237.43 mi (382.10 km) |
| Hertford to Ormesson-sur-Marne | 237.88 mi (382.84 km) |
| Hertford to Orsay | 236.29 mi (380.27 km) |
