| Philadelphia to Smolyan | 4,891.92 mi (7,872.78 km) |
| Philadelphia to Sofia | 4,789.63 mi (7,708.16 km) |
| Philadelphia to Sopot | 4,849.81 mi (7,805.01 km) |
| Philadelphia to Sozopol | 4,978.81 mi (8,012.61 km) |
| Philadelphia to Sredets | 4,961.59 mi (7,984.91 km) |
| Philadelphia to Stamboliyski | 4,862.27 mi (7,825.07 km) |
| Philadelphia to Stara Zagora | 4,895.43 mi (7,878.43 km) |
| Philadelphia to Svilengrad | 4,945.81 mi (7,959.51 km) |
| Philadelphia to Svishtov | 4,834.16 mi (7,779.83 km) |
| Philadelphia to Targovishte | 4,898.80 mi (7,883.85 km) |
| Philadelphia to Teteven | 4,819.15 mi (7,755.67 km) |
| Philadelphia to Troyan | 4,838.83 mi (7,787.35 km) |
| Philadelphia to Tryavna | 4,871.27 mi (7,839.56 km) |
| Philadelphia to Tutrakan | 4,866.58 mi (7,832.00 km) |
| Philadelphia to Varna | 4,953.22 mi (7,971.44 km) |
