| Greenford to Octeville | 143.22 mi (230.49 km) |
| Greenford to Oignies | 162.75 mi (261.91 km) |
| Greenford to Oissel | 163.92 mi (263.80 km) |
| Greenford to Olivet | 272.48 mi (438.52 km) |
| Greenford to Ollioules | 647.71 mi (1,042.38 km) |
| Greenford to Olonne-sur-Mer | 351.00 mi (564.88 km) |
| Greenford to Oloron-Sainte-Marie | 576.07 mi (927.09 km) |
| Greenford to Onet Village | 513.28 mi (826.05 km) |
| Greenford to Onnaing | 189.00 mi (304.16 km) |
| Greenford to Orange | 563.63 mi (907.07 km) |
| Greenford to Orchies | 172.37 mi (277.41 km) |
| Greenford to Orleans | 270.13 mi (434.73 km) |
| Greenford to Orly | 227.55 mi (366.20 km) |
| Greenford to Ormesson-sur-Marne | 228.61 mi (367.91 km) |
| Greenford to Orsay | 225.60 mi (363.07 km) |
