| Mount Prospect to Smolyan | 5,295.91 mi (8,522.94 km) |
| Mount Prospect to Sofia | 5,191.74 mi (8,355.30 km) |
| Mount Prospect to Sopot | 5,245.46 mi (8,441.75 km) |
| Mount Prospect to Sozopol | 5,361.54 mi (8,628.57 km) |
| Mount Prospect to Sredets | 5,347.36 mi (8,605.74 km) |
| Mount Prospect to Stamboliyski | 5,262.92 mi (8,469.85 km) |
| Mount Prospect to Stara Zagora | 5,288.31 mi (8,510.72 km) |
| Mount Prospect to Svilengrad | 5,340.99 mi (8,595.49 km) |
| Mount Prospect to Svishtov | 5,219.44 mi (8,399.87 km) |
| Mount Prospect to Targovishte | 5,280.83 mi (8,498.67 km) |
| Mount Prospect to Teteven | 5,215.09 mi (8,392.88 km) |
| Mount Prospect to Troyan | 5,232.86 mi (8,421.47 km) |
| Mount Prospect to Tryavna | 5,261.59 mi (8,467.72 km) |
| Mount Prospect to Tutrakan | 5,242.28 mi (8,436.63 km) |
| Mount Prospect to Varna | 5,328.81 mi (8,575.90 km) |
