| Cayce to Smolyan | 5,412.12 mi (8,709.97 km) |
| Cayce to Sofia | 5,310.42 mi (8,546.29 km) |
| Cayce to Sopot | 5,371.62 mi (8,644.78 km) |
| Cayce to Sozopol | 5,502.44 mi (8,855.33 km) |
| Cayce to Sredets | 5,484.79 mi (8,826.92 km) |
| Cayce to Stamboliyski | 5,383.16 mi (8,663.37 km) |
| Cayce to Stara Zagora | 5,417.61 mi (8,718.80 km) |
| Cayce to Svilengrad | 5,467.49 mi (8,799.08 km) |
| Cayce to Svishtov | 5,357.69 mi (8,622.36 km) |
| Cayce to Targovishte | 5,422.69 mi (8,726.98 km) |
| Cayce to Teteven | 5,340.97 mi (8,595.46 km) |
| Cayce to Troyan | 5,360.94 mi (8,627.61 km) |
| Cayce to Tryavna | 5,393.93 mi (8,680.69 km) |
| Cayce to Tutrakan | 5,391.43 mi (8,676.67 km) |
| Cayce to Varna | 5,477.94 mi (8,815.90 km) |
