| Caerfyrddin to Smolyan | 1,532.69 mi (2,466.63 km) |
| Caerfyrddin to Sofia | 1,430.32 mi (2,301.88 km) |
| Caerfyrddin to Sopot | 1,491.00 mi (2,399.53 km) |
| Caerfyrddin to Sozopol | 1,623.24 mi (2,612.35 km) |
| Caerfyrddin to Sredets | 1,604.95 mi (2,582.92 km) |
| Caerfyrddin to Stamboliyski | 1,502.98 mi (2,418.81 km) |
| Caerfyrddin to Stara Zagora | 1,537.03 mi (2,473.60 km) |
| Caerfyrddin to Svilengrad | 1,586.90 mi (2,553.86 km) |
| Caerfyrddin to Svishtov | 1,478.47 mi (2,379.36 km) |
| Caerfyrddin to Targovishte | 1,544.10 mi (2,484.99 km) |
| Caerfyrddin to Teteven | 1,460.35 mi (2,350.21 km) |
| Caerfyrddin to Troyan | 1,480.35 mi (2,382.39 km) |
| Caerfyrddin to Tryavna | 1,513.59 mi (2,435.89 km) |
| Caerfyrddin to Tutrakan | 1,515.69 mi (2,439.27 km) |
| Caerfyrddin to Varna | 1,601.45 mi (2,577.29 km) |
