| Swansea to Orbetello | 4,977.03 mi (8,009.76 km) |
| Swansea to Oria | 5,321.05 mi (8,563.40 km) |
| Swansea to Oristano | 4,969.25 mi (7,997.24 km) |
| Swansea to Orta Nova | 5,207.11 mi (8,380.04 km) |
| Swansea to Orte | 5,024.24 mi (8,085.73 km) |
| Swansea to Ortona | 5,110.46 mi (8,224.49 km) |
| Swansea to Orvieto | 5,002.33 mi (8,050.47 km) |
| Swansea to Orzinuovi | 4,806.46 mi (7,735.25 km) |
| Swansea to Osimo | 5,025.94 mi (8,088.46 km) |
| Swansea to Ospitaletto | 4,805.92 mi (7,734.38 km) |
| Swansea to Ostuni | 5,308.67 mi (8,543.48 km) |
| Swansea to Ottaviano | 5,177.66 mi (8,332.63 km) |
| Swansea to Ovada | 4,784.38 mi (7,699.72 km) |
| Swansea to Ozieri | 4,959.61 mi (7,981.73 km) |
| Swansea to Paceco | 5,219.12 mi (8,399.36 km) |
