| Blackwells Mills to Smolyan | 4,849.58 mi (7,804.65 km) |
| Blackwells Mills to Sofia | 4,747.25 mi (7,639.96 km) |
| Blackwells Mills to Sopot | 4,807.35 mi (7,736.69 km) |
| Blackwells Mills to Sozopol | 4,936.21 mi (7,944.06 km) |
| Blackwells Mills to Sredets | 4,919.03 mi (7,916.41 km) |
| Blackwells Mills to Stamboliyski | 4,819.89 mi (7,756.86 km) |
| Blackwells Mills to Stara Zagora | 4,852.94 mi (7,810.05 km) |
| Blackwells Mills to Svilengrad | 4,903.36 mi (7,891.20 km) |
| Blackwells Mills to Svishtov | 4,791.57 mi (7,711.29 km) |
| Blackwells Mills to Targovishte | 4,856.18 mi (7,815.27 km) |
| Blackwells Mills to Teteven | 4,776.69 mi (7,687.34 km) |
| Blackwells Mills to Troyan | 4,796.36 mi (7,718.99 km) |
| Blackwells Mills to Tryavna | 4,828.75 mi (7,771.13 km) |
| Blackwells Mills to Tutrakan | 4,823.89 mi (7,763.31 km) |
| Blackwells Mills to Varna | 4,910.55 mi (7,902.77 km) |
