| Billdal to Smolyan | 1,239.93 mi (1,995.48 km) |
| Billdal to Sofia | 1,141.94 mi (1,837.78 km) |
| Billdal to Sopot | 1,173.26 mi (1,888.18 km) |
| Billdal to Sozopol | 1,253.60 mi (2,017.47 km) |
| Billdal to Sredets | 1,245.90 mi (2,005.08 km) |
| Billdal to Stamboliyski | 1,201.58 mi (1,933.75 km) |
| Billdal to Stara Zagora | 1,205.92 mi (1,940.74 km) |
| Billdal to Svilengrad | 1,259.58 mi (2,027.10 km) |
| Billdal to Svishtov | 1,125.67 mi (1,811.58 km) |
| Billdal to Targovishte | 1,176.31 mi (1,893.08 km) |
| Billdal to Teteven | 1,146.50 mi (1,845.11 km) |
| Billdal to Troyan | 1,157.86 mi (1,863.39 km) |
| Billdal to Tryavna | 1,175.57 mi (1,891.90 km) |
| Billdal to Tutrakan | 1,128.40 mi (1,815.98 km) |
| Billdal to Varna | 1,210.34 mi (1,947.86 km) |
