| Porsgrunn to Smolyan | 1,372.70 mi (2,209.15 km) |
| Porsgrunn to Sofia | 1,274.41 mi (2,050.97 km) |
| Porsgrunn to Sopot | 1,306.21 mi (2,102.13 km) |
| Porsgrunn to Sozopol | 1,386.39 mi (2,231.18 km) |
| Porsgrunn to Sredets | 1,378.83 mi (2,219.01 km) |
| Porsgrunn to Stamboliyski | 1,334.39 mi (2,147.50 km) |
| Porsgrunn to Stara Zagora | 1,338.96 mi (2,154.85 km) |
| Porsgrunn to Svilengrad | 1,392.63 mi (2,241.22 km) |
| Porsgrunn to Svishtov | 1,258.71 mi (2,025.70 km) |
| Porsgrunn to Targovishte | 1,309.23 mi (2,107.00 km) |
| Porsgrunn to Teteven | 1,279.37 mi (2,058.95 km) |
| Porsgrunn to Troyan | 1,290.83 mi (2,077.39 km) |
| Porsgrunn to Tryavna | 1,308.62 mi (2,106.02 km) |
| Porsgrunn to Tutrakan | 1,261.15 mi (2,029.63 km) |
| Porsgrunn to Varna | 1,342.84 mi (2,161.10 km) |
