| Ruislip to Olivares | 1,017.29 mi (1,637.16 km) |
| Ruislip to Olivenza | 947.10 mi (1,524.21 km) |
| Ruislip to Olot | 663.41 mi (1,067.66 km) |
| Ruislip to Onate | 597.45 mi (961.51 km) |
| Ruislip to Onda | 802.46 mi (1,291.43 km) |
| Ruislip to Onteniente | 881.24 mi (1,418.22 km) |
| Ruislip to Orihuela | 932.43 mi (1,500.60 km) |
| Ruislip to Osuna | 1,016.87 mi (1,636.50 km) |
| Ruislip to Ourense | 727.37 mi (1,170.58 km) |
| Ruislip to Oviedo | 620.98 mi (999.38 km) |
| Ruislip to Paiporta | 839.36 mi (1,350.82 km) |
| Ruislip to Pajara | 1,753.73 mi (2,822.35 km) |
| Ruislip to Palafolls | 700.79 mi (1,127.81 km) |
| Ruislip to Palafrugell | 688.50 mi (1,108.03 km) |
| Ruislip to Palamos | 692.93 mi (1,115.16 km) |
