| Castleton to Olivares | 1,133.53 mi (1,824.24 km) |
| Castleton to Olivenza | 1,055.86 mi (1,699.24 km) |
| Castleton to Olot | 816.87 mi (1,314.63 km) |
| Castleton to Onate | 729.53 mi (1,174.06 km) |
| Castleton to Onda | 945.85 mi (1,522.20 km) |
| Castleton to Onteniente | 1,023.08 mi (1,646.50 km) |
| Castleton to Orihuela | 1,072.88 mi (1,726.64 km) |
| Castleton to Osuna | 1,138.82 mi (1,832.75 km) |
| Castleton to Ourense | 820.29 mi (1,320.12 km) |
| Castleton to Oviedo | 726.35 mi (1,168.94 km) |
| Castleton to Paiporta | 982.04 mi (1,580.44 km) |
| Castleton to Pajara | 1,845.87 mi (2,970.64 km) |
| Castleton to Palafolls | 854.49 mi (1,375.17 km) |
| Castleton to Palafrugell | 843.19 mi (1,356.98 km) |
| Castleton to Palamos | 847.51 mi (1,363.93 km) |
