| Key West to Smolyan | 5,889.63 mi (9,478.44 km) |
| Key West to Sofia | 5,791.16 mi (9,319.97 km) |
| Key West to Sopot | 5,856.24 mi (9,424.70 km) |
| Key West to Sozopol | 5,994.52 mi (9,647.25 km) |
| Key West to Sredets | 5,974.92 mi (9,615.71 km) |
| Key West to Stamboliyski | 5,863.77 mi (9,436.83 km) |
| Key West to Stara Zagora | 5,903.54 mi (9,500.83 km) |
| Key West to Svilengrad | 5,950.84 mi (9,576.95 km) |
| Key West to Svishtov | 5,850.26 mi (9,415.09 km) |
| Key West to Targovishte | 5,916.58 mi (9,521.81 km) |
| Key West to Teteven | 5,825.89 mi (9,375.86 km) |
| Key West to Troyan | 5,846.98 mi (9,409.80 km) |
| Key West to Tryavna | 5,882.18 mi (9,466.46 km) |
| Key West to Tutrakan | 5,890.37 mi (9,479.63 km) |
| Key West to Varna | 5,975.59 mi (9,616.79 km) |
