| Willow Grove to Smolyan | 4,885.23 mi (7,862.01 km) |
| Willow Grove to Sofia | 4,782.90 mi (7,697.33 km) |
| Willow Grove to Sopot | 4,843.00 mi (7,794.06 km) |
| Willow Grove to Sozopol | 4,971.86 mi (8,001.44 km) |
| Willow Grove to Sredets | 4,954.68 mi (7,973.78 km) |
| Willow Grove to Stamboliyski | 4,855.53 mi (7,814.23 km) |
| Willow Grove to Stara Zagora | 4,888.59 mi (7,867.43 km) |
| Willow Grove to Svilengrad | 4,939.01 mi (7,948.57 km) |
| Willow Grove to Svishtov | 4,827.22 mi (7,768.67 km) |
| Willow Grove to Targovishte | 4,891.83 mi (7,872.64 km) |
| Willow Grove to Teteven | 4,812.34 mi (7,744.72 km) |
| Willow Grove to Troyan | 4,832.01 mi (7,776.37 km) |
| Willow Grove to Tryavna | 4,864.41 mi (7,828.50 km) |
| Willow Grove to Tutrakan | 4,859.53 mi (7,820.66 km) |
| Willow Grove to Varna | 4,946.19 mi (7,960.12 km) |
