| Boston to Popovo | 1,369.55 mi (2,204.08 km) |
| Boston to Provadia | 1,424.18 mi (2,291.99 km) |
| Boston to Radnevo | 1,403.89 mi (2,259.35 km) |
| Boston to Radomir | 1,278.31 mi (2,057.24 km) |
| Boston to Rakitovo | 1,347.51 mi (2,168.60 km) |
| Boston to Rakovski | 1,367.06 mi (2,200.07 km) |
| Boston to Razgrad | 1,372.97 mi (2,209.59 km) |
| Boston to Razlog | 1,328.99 mi (2,138.80 km) |
| Boston to Ruse | 1,338.47 mi (2,154.06 km) |
| Boston to Samokov | 1,311.06 mi (2,109.94 km) |
| Boston to Sandanski | 1,337.14 mi (2,151.91 km) |
| Boston to Sevlievo | 1,339.73 mi (2,156.08 km) |
| Boston to Shumen | 1,400.08 mi (2,253.22 km) |
| Boston to Silistra | 1,378.46 mi (2,218.42 km) |
| Boston to Sliven | 1,402.42 mi (2,256.97 km) |
