| Swansea to Sestu | 5,015.35 mi (8,071.42 km) |
| Swansea to Settimo Torinese | 4,729.60 mi (7,611.55 km) |
| Swansea to Seveso | 4,765.17 mi (7,668.80 km) |
| Swansea to Sezze | 5,092.18 mi (8,195.07 km) |
| Swansea to Siano | 5,188.58 mi (8,350.21 km) |
| Swansea to Siena | 4,946.06 mi (7,959.92 km) |
| Swansea to Signa | 4,917.82 mi (7,914.47 km) |
| Swansea to Silea | 4,889.60 mi (7,869.06 km) |
| Swansea to Silvi Paese | 5,090.58 mi (8,192.49 km) |
| Swansea to Sinalunga | 4,966.53 mi (7,992.85 km) |
| Swansea to Siniscola | 4,989.55 mi (8,029.91 km) |
| Swansea to Sinnai | 5,020.03 mi (8,078.96 km) |
| Swansea to Siracusa | 5,375.65 mi (8,651.27 km) |
| Swansea to Solaro | 4,764.13 mi (7,667.13 km) |
| Swansea to Soliera | 4,872.32 mi (7,841.24 km) |
