| Gundelfingen to Smolyan | 935.27 mi (1,505.18 km) |
| Gundelfingen to Sofia | 834.44 mi (1,342.90 km) |
| Gundelfingen to Sopot | 898.10 mi (1,445.34 km) |
| Gundelfingen to Sozopol | 1,036.75 mi (1,668.49 km) |
| Gundelfingen to Sredets | 1,016.69 mi (1,636.21 km) |
| Gundelfingen to Stamboliyski | 907.24 mi (1,460.06 km) |
| Gundelfingen to Stara Zagora | 945.21 mi (1,521.16 km) |
| Gundelfingen to Svilengrad | 993.19 mi (1,598.38 km) |
| Gundelfingen to Svishtov | 893.18 mi (1,437.43 km) |
| Gundelfingen to Targovishte | 959.87 mi (1,544.76 km) |
| Gundelfingen to Teteven | 867.66 mi (1,396.36 km) |
| Gundelfingen to Troyan | 888.60 mi (1,430.06 km) |
| Gundelfingen to Tryavna | 923.79 mi (1,486.70 km) |
| Gundelfingen to Tutrakan | 937.85 mi (1,509.33 km) |
| Gundelfingen to Varna | 1,021.05 mi (1,643.21 km) |
