| Idstein to Smolyan | 986.27 mi (1,587.24 km) |
| Idstein to Sofia | 882.47 mi (1,420.21 km) |
| Idstein to Sopot | 939.68 mi (1,512.27 km) |
| Idstein to Sozopol | 1,067.71 mi (1,718.32 km) |
| Idstein to Sredets | 1,050.22 mi (1,690.16 km) |
| Idstein to Stamboliyski | 954.43 mi (1,536.00 km) |
| Idstein to Stara Zagora | 984.63 mi (1,584.60 km) |
| Idstein to Svilengrad | 1,035.76 mi (1,666.89 km) |
| Idstein to Svishtov | 922.96 mi (1,485.36 km) |
| Idstein to Targovishte | 988.03 mi (1,590.09 km) |
| Idstein to Teteven | 909.05 mi (1,462.97 km) |
| Idstein to Troyan | 928.20 mi (1,493.79 km) |
| Idstein to Tryavna | 960.01 mi (1,544.99 km) |
| Idstein to Tutrakan | 958.34 mi (1,542.29 km) |
| Idstein to Varna | 1,044.36 mi (1,680.73 km) |
