| Gurnee to Smolyan | 5,281.04 mi (8,499.02 km) |
| Gurnee to Sofia | 5,176.86 mi (8,331.35 km) |
| Gurnee to Sopot | 5,230.39 mi (8,417.49 km) |
| Gurnee to Sozopol | 5,346.10 mi (8,603.71 km) |
| Gurnee to Sredets | 5,332.00 mi (8,581.02 km) |
| Gurnee to Stamboliyski | 5,247.97 mi (8,445.80 km) |
| Gurnee to Stara Zagora | 5,273.15 mi (8,486.32 km) |
| Gurnee to Svilengrad | 5,325.88 mi (8,571.17 km) |
| Gurnee to Svishtov | 5,204.10 mi (8,375.19 km) |
| Gurnee to Targovishte | 5,265.39 mi (8,473.83 km) |
| Gurnee to Teteven | 5,200.04 mi (8,368.65 km) |
| Gurnee to Troyan | 5,217.74 mi (8,397.15 km) |
| Gurnee to Tryavna | 5,246.37 mi (8,443.22 km) |
| Gurnee to Tutrakan | 5,226.69 mi (8,411.54 km) |
| Gurnee to Varna | 5,313.20 mi (8,550.77 km) |
