| Milford Haven to Olivares | 989.33 mi (1,592.18 km) |
| Milford Haven to Olivenza | 905.64 mi (1,457.48 km) |
| Milford Haven to Olot | 747.37 mi (1,202.78 km) |
| Milford Haven to Onate | 612.14 mi (985.14 km) |
| Milford Haven to Onda | 843.45 mi (1,357.40 km) |
| Milford Haven to Onteniente | 916.05 mi (1,474.24 km) |
| Milford Haven to Orihuela | 962.35 mi (1,548.75 km) |
| Milford Haven to Osuna | 1,000.54 mi (1,610.21 km) |
| Milford Haven to Ourense | 661.29 mi (1,064.24 km) |
| Milford Haven to Oviedo | 578.42 mi (930.88 km) |
| Milford Haven to Paiporta | 877.42 mi (1,412.07 km) |
| Milford Haven to Pajara | 1,680.89 mi (2,705.12 km) |
| Milford Haven to Palafolls | 785.15 mi (1,263.58 km) |
| Milford Haven to Palafrugell | 779.09 mi (1,253.82 km) |
| Milford Haven to Palamos | 782.71 mi (1,259.65 km) |
