| Socorro to Smolyan | 6,492.99 mi (10,449.45 km) |
| Socorro to Sofia | 6,388.73 mi (10,281.67 km) |
| Socorro to Sopot | 6,438.25 mi (10,361.36 km) |
| Socorro to Sozopol | 6,545.29 mi (10,533.63 km) |
| Socorro to Sredets | 6,533.16 mi (10,514.11 km) |
| Socorro to Stamboliyski | 6,458.42 mi (10,393.82 km) |
| Socorro to Stara Zagora | 6,479.05 mi (10,427.02 km) |
| Socorro to Svilengrad | 6,532.56 mi (10,513.13 km) |
| Socorro to Svishtov | 6,406.32 mi (10,309.98 km) |
| Socorro to Targovishte | 6,465.04 mi (10,404.47 km) |
| Socorro to Teteven | 6,408.35 mi (10,313.25 km) |
| Socorro to Troyan | 6,424.82 mi (10,339.76 km) |
| Socorro to Tryavna | 6,451.07 mi (10,382.00 km) |
| Socorro to Tutrakan | 6,422.94 mi (10,336.72 km) |
| Socorro to Varna | 6,508.38 mi (10,474.23 km) |
