| Keflavik to Smolyan | 2,419.34 mi (3,893.56 km) |
| Keflavik to Sofia | 2,316.02 mi (3,727.28 km) |
| Keflavik to Sopot | 2,360.10 mi (3,798.21 km) |
| Keflavik to Sozopol | 2,459.83 mi (3,958.71 km) |
| Keflavik to Sredets | 2,448.85 mi (3,941.04 km) |
| Keflavik to Stamboliyski | 2,383.12 mi (3,835.26 km) |
| Keflavik to Stara Zagora | 2,398.64 mi (3,860.24 km) |
| Keflavik to Svilengrad | 2,452.55 mi (3,947.00 km) |
| Keflavik to Svishtov | 2,323.26 mi (3,738.93 km) |
| Keflavik to Targovishte | 2,380.08 mi (3,830.36 km) |
| Keflavik to Teteven | 2,330.93 mi (3,751.27 km) |
| Keflavik to Troyan | 2,345.94 mi (3,775.42 km) |
| Keflavik to Tryavna | 2,369.76 mi (3,813.76 km) |
| Keflavik to Tutrakan | 2,336.47 mi (3,760.18 km) |
| Keflavik to Varna | 2,421.36 mi (3,896.80 km) |
