| Skien to Smolyan | 1,381.13 mi (2,222.71 km) |
| Skien to Sofia | 1,282.81 mi (2,064.49 km) |
| Skien to Sopot | 1,314.65 mi (2,115.73 km) |
| Skien to Sozopol | 1,394.87 mi (2,244.82 km) |
| Skien to Sredets | 1,387.30 mi (2,232.65 km) |
| Skien to Stamboliyski | 1,342.82 mi (2,161.07 km) |
| Skien to Stara Zagora | 1,347.42 mi (2,168.47 km) |
| Skien to Svilengrad | 1,401.09 mi (2,254.84 km) |
| Skien to Svishtov | 1,267.18 mi (2,039.33 km) |
| Skien to Targovishte | 1,317.70 mi (2,120.64 km) |
| Skien to Teteven | 1,287.81 mi (2,072.53 km) |
| Skien to Troyan | 1,299.28 mi (2,090.98 km) |
| Skien to Tryavna | 1,317.08 mi (2,119.64 km) |
| Skien to Tutrakan | 1,269.63 mi (2,043.26 km) |
| Skien to Varna | 1,351.31 mi (2,174.73 km) |
