| Sondershausen to Smolyan | 940.49 mi (1,513.57 km) |
| Sondershausen to Sofia | 836.30 mi (1,345.89 km) |
| Sondershausen to Sopot | 886.44 mi (1,426.58 km) |
| Sondershausen to Sozopol | 1,003.01 mi (1,614.18 km) |
| Sondershausen to Sredets | 987.95 mi (1,589.95 km) |
| Sondershausen to Stamboliyski | 905.85 mi (1,457.83 km) |
| Sondershausen to Stara Zagora | 928.58 mi (1,494.40 km) |
| Sondershausen to Svilengrad | 981.53 mi (1,579.62 km) |
| Sondershausen to Svishtov | 859.90 mi (1,383.87 km) |
| Sondershausen to Targovishte | 922.34 mi (1,484.36 km) |
| Sondershausen to Teteven | 856.30 mi (1,378.09 km) |
| Sondershausen to Troyan | 873.45 mi (1,405.69 km) |
| Sondershausen to Tryavna | 901.67 mi (1,451.10 km) |
| Sondershausen to Tutrakan | 886.88 mi (1,427.30 km) |
| Sondershausen to Varna | 973.71 mi (1,567.04 km) |
