| Prairie Ridge to Popovo | 5,893.13 mi (9,484.08 km) |
| Prairie Ridge to Provadia | 5,925.15 mi (9,535.60 km) |
| Prairie Ridge to Radnevo | 5,955.38 mi (9,584.26 km) |
| Prairie Ridge to Radomir | 5,882.22 mi (9,466.52 km) |
| Prairie Ridge to Rakitovo | 5,940.66 mi (9,560.57 km) |
| Prairie Ridge to Rakovski | 5,938.05 mi (9,556.37 km) |
| Prairie Ridge to Razgrad | 5,886.37 mi (9,473.20 km) |
| Prairie Ridge to Razlog | 5,934.93 mi (9,551.35 km) |
| Prairie Ridge to Ruse | 5,857.60 mi (9,426.90 km) |
| Prairie Ridge to Samokov | 5,907.74 mi (9,507.60 km) |
| Prairie Ridge to Sandanski | 5,951.35 mi (9,577.78 km) |
| Prairie Ridge to Sevlievo | 5,893.50 mi (9,484.68 km) |
| Prairie Ridge to Shumen | 5,909.91 mi (9,511.08 km) |
| Prairie Ridge to Silistra | 5,861.63 mi (9,433.37 km) |
| Prairie Ridge to Sliven | 5,937.96 mi (9,556.23 km) |
