| Willoughby to Popovo | 5,047.49 mi (8,123.15 km) |
| Willoughby to Provadia | 5,099.93 mi (8,207.55 km) |
| Willoughby to Radnevo | 5,084.65 mi (8,182.96 km) |
| Willoughby to Radomir | 4,958.72 mi (7,980.29 km) |
| Willoughby to Rakitovo | 5,028.19 mi (8,092.08 km) |
| Willoughby to Rakovski | 5,048.26 mi (8,124.39 km) |
| Willoughby to Razgrad | 5,049.60 mi (8,126.55 km) |
| Willoughby to Razlog | 5,008.76 mi (8,060.82 km) |
| Willoughby to Ruse | 5,015.29 mi (8,071.33 km) |
| Willoughby to Samokov | 4,991.74 mi (8,033.44 km) |
| Willoughby to Sandanski | 5,015.78 mi (8,072.12 km) |
| Willoughby to Sevlievo | 5,020.20 mi (8,079.24 km) |
| Willoughby to Shumen | 5,076.69 mi (8,170.15 km) |
| Willoughby to Silistra | 5,050.03 mi (8,127.24 km) |
| Willoughby to Sliven | 5,082.06 mi (8,178.79 km) |
