| Holyhead to Sesena | 913.46 mi (1,470.07 km) |
| Holyhead to Sestao | 694.80 mi (1,118.17 km) |
| Holyhead to Sevilla | 1,112.17 mi (1,789.86 km) |
| Holyhead to Sevilla La Nueva | 896.00 mi (1,441.97 km) |
| Holyhead to Silla | 984.04 mi (1,583.67 km) |
| Holyhead to Silleda | 751.42 mi (1,209.29 km) |
| Holyhead to Sitges | 886.32 mi (1,426.40 km) |
| Holyhead to Socuellamos | 972.28 mi (1,564.73 km) |
| Holyhead to Soller | 997.20 mi (1,604.85 km) |
| Holyhead to Solsona | 831.77 mi (1,338.60 km) |
| Holyhead to Son Servera | 1,017.87 mi (1,638.10 km) |
| Holyhead to Sonseca | 940.84 mi (1,514.14 km) |
| Holyhead to Sopelana | 690.07 mi (1,110.56 km) |
| Holyhead to Soria | 803.77 mi (1,293.55 km) |
| Holyhead to Suances | 682.86 mi (1,098.96 km) |
