| Douai to Smolyan | 1,196.16 mi (1,925.04 km) |
| Douai to Sofia | 1,093.71 mi (1,760.15 km) |
| Douai to Sopot | 1,154.46 mi (1,857.92 km) |
| Douai to Sozopol | 1,287.58 mi (2,072.15 km) |
| Douai to Sredets | 1,268.99 mi (2,042.24 km) |
| Douai to Stamboliyski | 1,166.36 mi (1,877.07 km) |
| Douai to Stara Zagora | 1,200.58 mi (1,932.15 km) |
| Douai to Svilengrad | 1,250.32 mi (2,012.20 km) |
| Douai to Svishtov | 1,142.88 mi (1,839.29 km) |
| Douai to Targovishte | 1,208.77 mi (1,945.33 km) |
| Douai to Teteven | 1,123.81 mi (1,808.61 km) |
| Douai to Troyan | 1,143.89 mi (1,840.92 km) |
| Douai to Tryavna | 1,177.36 mi (1,894.78 km) |
| Douai to Tutrakan | 1,181.65 mi (1,901.67 km) |
| Douai to Varna | 1,266.97 mi (2,038.99 km) |
