| Drogheda to Smolyan | 1,651.55 mi (2,657.92 km) |
| Drogheda to Sofia | 1,548.09 mi (2,491.41 km) |
| Drogheda to Sopot | 1,605.96 mi (2,584.54 km) |
| Drogheda to Sozopol | 1,732.99 mi (2,788.98 km) |
| Drogheda to Sredets | 1,715.97 mi (2,761.58 km) |
| Drogheda to Stamboliyski | 1,620.28 mi (2,607.58 km) |
| Drogheda to Stara Zagora | 1,650.92 mi (2,656.89 km) |
| Drogheda to Svilengrad | 1,702.04 mi (2,739.16 km) |
| Drogheda to Svishtov | 1,588.40 mi (2,556.27 km) |
| Drogheda to Targovishte | 1,652.95 mi (2,660.17 km) |
| Drogheda to Teteven | 1,575.32 mi (2,535.23 km) |
| Drogheda to Troyan | 1,594.50 mi (2,566.10 km) |
| Drogheda to Tryavna | 1,626.17 mi (2,617.07 km) |
| Drogheda to Tutrakan | 1,621.21 mi (2,609.09 km) |
| Drogheda to Varna | 1,707.73 mi (2,748.33 km) |
