| Boo to Smolyan | 1,256.28 mi (2,021.79 km) |
| Boo to Sofia | 1,168.32 mi (1,880.23 km) |
| Boo to Sopot | 1,184.40 mi (1,906.11 km) |
| Boo to Sozopol | 1,235.40 mi (1,988.18 km) |
| Boo to Sredets | 1,233.05 mi (1,984.40 km) |
| Boo to Stamboliyski | 1,217.35 mi (1,959.13 km) |
| Boo to Stara Zagora | 1,208.55 mi (1,944.98 km) |
| Boo to Svilengrad | 1,259.73 mi (2,027.33 km) |
| Boo to Svishtov | 1,125.46 mi (1,811.26 km) |
| Boo to Targovishte | 1,164.92 mi (1,874.76 km) |
| Boo to Teteven | 1,161.65 mi (1,869.49 km) |
| Boo to Troyan | 1,168.27 mi (1,880.14 km) |
| Boo to Tryavna | 1,177.65 mi (1,895.25 km) |
| Boo to Tutrakan | 1,112.00 mi (1,789.59 km) |
| Boo to Varna | 1,185.45 mi (1,907.80 km) |
