| Merthyr Tudful to Solofra | 1,145.63 mi (1,843.72 km) |
| Merthyr Tudful to Somma Lombardo | 690.27 mi (1,110.89 km) |
| Merthyr Tudful to Somma Vesuviana | 1,129.04 mi (1,817.02 km) |
| Merthyr Tudful to Sommacampagna | 782.22 mi (1,258.86 km) |
| Merthyr Tudful to Sona | 780.14 mi (1,255.51 km) |
| Merthyr Tudful to Sondrio | 712.19 mi (1,146.16 km) |
| Merthyr Tudful to Sora | 1,057.32 mi (1,701.58 km) |
| Merthyr Tudful to Sorbolo | 792.21 mi (1,274.94 km) |
| Merthyr Tudful to Soresina | 750.43 mi (1,207.71 km) |
| Merthyr Tudful to Sorisole | 722.82 mi (1,163.27 km) |
| Merthyr Tudful to Sorrento | 1,139.39 mi (1,833.67 km) |
| Merthyr Tudful to Sorso | 944.99 mi (1,520.82 km) |
| Merthyr Tudful to Sortino | 1,348.32 mi (2,169.91 km) |
| Merthyr Tudful to Soverato Marina | 1,316.72 mi (2,119.06 km) |
| Merthyr Tudful to Sovicille | 895.18 mi (1,440.66 km) |
