| Swansea to Oskaloosa (Iowa) | 235.91 mi (379.66 km) |
| Swansea to Oswego (Illinois) | 233.31 mi (375.47 km) |
| Swansea to Oswego (New York) | 779.20 mi (1,254.01 km) |
| Swansea to Otsego (Minnesota) | 500.06 mi (804.77 km) |
| Swansea to Ottawa (Illinois) | 203.29 mi (327.16 km) |
| Swansea to Ottawa (Kansas) | 285.07 mi (458.77 km) |
| Swansea to Ottumwa (Iowa) | 213.94 mi (344.31 km) |
| Swansea to Overland (Missouri) | 23.01 mi (37.02 km) |
| Swansea to Overland Park (Kansas) | 254.47 mi (409.53 km) |
| Swansea to Overlea (Maryland) | 725.13 mi (1,166.98 km) |
| Swansea to Oviedo (Florida) | 849.66 mi (1,367.40 km) |
| Swansea to Owasso (Oklahoma) | 356.74 mi (574.11 km) |
| Swansea to Owatonna (Minnesota) | 418.12 mi (672.91 km) |
| Swansea to Owensboro (Kentucky) | 165.20 mi (265.87 km) |
| Swansea to Owings Mills (Maryland) | 710.53 mi (1,143.48 km) |
