| Birkenfeld to Smolyan | 926.92 mi (1,491.73 km) |
| Birkenfeld to Sofia | 824.34 mi (1,326.64 km) |
| Birkenfeld to Sopot | 885.16 mi (1,424.53 km) |
| Birkenfeld to Sozopol | 1,019.36 mi (1,640.49 km) |
| Birkenfeld to Sredets | 1,000.40 mi (1,609.99 km) |
| Birkenfeld to Stamboliyski | 896.97 mi (1,443.54 km) |
| Birkenfeld to Stara Zagora | 931.41 mi (1,498.96 km) |
| Birkenfeld to Svilengrad | 980.99 mi (1,578.75 km) |
| Birkenfeld to Svishtov | 874.83 mi (1,407.91 km) |
| Birkenfeld to Targovishte | 941.01 mi (1,514.42 km) |
| Birkenfeld to Teteven | 854.53 mi (1,375.24 km) |
| Birkenfeld to Troyan | 874.71 mi (1,407.71 km) |
| Birkenfeld to Tryavna | 908.46 mi (1,462.02 km) |
| Birkenfeld to Tutrakan | 915.56 mi (1,473.46 km) |
| Birkenfeld to Varna | 1,000.23 mi (1,609.71 km) |
