| Greenock to Smolyan | 1,648.37 mi (2,652.79 km) |
| Greenock to Sofia | 1,544.09 mi (2,484.97 km) |
| Greenock to Sopot | 1,596.92 mi (2,570.00 km) |
| Greenock to Sozopol | 1,714.87 mi (2,759.82 km) |
| Greenock to Sredets | 1,699.88 mi (2,735.69 km) |
| Greenock to Stamboliyski | 1,614.83 mi (2,598.82 km) |
| Greenock to Stara Zagora | 1,639.80 mi (2,639.00 km) |
| Greenock to Svilengrad | 1,692.43 mi (2,723.71 km) |
| Greenock to Svishtov | 1,571.82 mi (2,529.61 km) |
| Greenock to Targovishte | 1,634.18 mi (2,629.96 km) |
| Greenock to Teteven | 1,566.58 mi (2,521.17 km) |
| Greenock to Troyan | 1,584.30 mi (2,549.69 km) |
| Greenock to Tryavna | 1,613.25 mi (2,596.27 km) |
| Greenock to Tutrakan | 1,597.88 mi (2,571.54 km) |
| Greenock to Varna | 1,684.71 mi (2,711.28 km) |
