| Hennef to Smolyan | 1,043.59 mi (1,679.49 km) |
| Hennef to Sofia | 939.68 mi (1,512.27 km) |
| Hennef to Sopot | 996.27 mi (1,603.34 km) |
| Hennef to Sozopol | 1,122.97 mi (1,807.25 km) |
| Hennef to Sredets | 1,105.81 mi (1,779.63 km) |
| Hennef to Stamboliyski | 1,011.48 mi (1,627.83 km) |
| Hennef to Stara Zagora | 1,040.94 mi (1,675.23 km) |
| Hennef to Svilengrad | 1,092.32 mi (1,757.92 km) |
| Hennef to Svishtov | 978.31 mi (1,574.44 km) |
| Hennef to Targovishte | 1,043.07 mi (1,678.66 km) |
| Hennef to Teteven | 965.66 mi (1,554.07 km) |
| Hennef to Troyan | 984.61 mi (1,584.57 km) |
| Hennef to Tryavna | 1,016.03 mi (1,635.14 km) |
| Hennef to Tutrakan | 1,012.40 mi (1,629.31 km) |
| Hennef to Varna | 1,098.66 mi (1,768.12 km) |
