| Boone to Popovo | 5,319.18 mi (8,560.40 km) |
| Boone to Provadia | 5,373.67 mi (8,648.09 km) |
| Boone to Radnevo | 5,351.88 mi (8,613.01 km) |
| Boone to Radomir | 5,220.16 mi (8,401.04 km) |
| Boone to Rakitovo | 5,290.02 mi (8,513.47 km) |
| Boone to Rakovski | 5,313.25 mi (8,550.85 km) |
| Boone to Razgrad | 5,322.57 mi (8,565.85 km) |
| Boone to Razlog | 5,268.81 mi (8,479.33 km) |
| Boone to Ruse | 5,288.08 mi (8,510.34 km) |
| Boone to Samokov | 5,253.73 mi (8,455.06 km) |
| Boone to Sandanski | 5,274.19 mi (8,487.99 km) |
| Boone to Sevlievo | 5,288.25 mi (8,510.62 km) |
| Boone to Shumen | 5,349.69 mi (8,609.49 km) |
| Boone to Silistra | 5,326.67 mi (8,572.45 km) |
| Boone to Sliven | 5,351.58 mi (8,612.53 km) |
