| Hartford to Smolyan | 4,716.31 mi (7,590.17 km) |
| Hartford to Sofia | 4,613.93 mi (7,425.40 km) |
| Hartford to Sopot | 4,673.94 mi (7,521.98 km) |
| Hartford to Sozopol | 4,802.67 mi (7,729.15 km) |
| Hartford to Sredets | 4,785.51 mi (7,701.53 km) |
| Hartford to Stamboliyski | 4,686.55 mi (7,542.27 km) |
| Hartford to Stara Zagora | 4,719.50 mi (7,595.30 km) |
| Hartford to Svilengrad | 4,769.96 mi (7,676.50 km) |
| Hartford to Svishtov | 4,658.04 mi (7,496.39 km) |
| Hartford to Targovishte | 4,722.63 mi (7,600.34 km) |
| Hartford to Teteven | 4,643.28 mi (7,472.63 km) |
| Hartford to Troyan | 4,662.92 mi (7,504.24 km) |
| Hartford to Tryavna | 4,695.28 mi (7,556.32 km) |
| Hartford to Tutrakan | 4,690.30 mi (7,548.31 km) |
| Hartford to Varna | 4,776.96 mi (7,687.77 km) |
