| Glenn Dale to Smolyan | 5,005.65 mi (8,055.82 km) |
| Glenn Dale to Sofia | 4,903.35 mi (7,891.19 km) |
| Glenn Dale to Sopot | 4,963.50 mi (7,987.99 km) |
| Glenn Dale to Sozopol | 5,092.41 mi (8,195.44 km) |
| Glenn Dale to Sredets | 5,075.22 mi (8,167.77 km) |
| Glenn Dale to Stamboliyski | 4,976.00 mi (8,008.09 km) |
| Glenn Dale to Stara Zagora | 5,009.11 mi (8,061.38 km) |
| Glenn Dale to Svilengrad | 5,059.51 mi (8,142.50 km) |
| Glenn Dale to Svishtov | 4,947.77 mi (7,962.67 km) |
| Glenn Dale to Targovishte | 5,012.38 mi (8,066.65 km) |
| Glenn Dale to Teteven | 4,932.84 mi (7,938.64 km) |
| Glenn Dale to Troyan | 4,952.52 mi (7,970.31 km) |
| Glenn Dale to Tryavna | 4,984.93 mi (8,022.48 km) |
| Glenn Dale to Tutrakan | 4,980.08 mi (8,014.67 km) |
| Glenn Dale to Varna | 5,066.74 mi (8,154.13 km) |
