| Erkrath to Popovo | 1,051.53 mi (1,692.28 km) |
| Erkrath to Provadia | 1,106.41 mi (1,780.59 km) |
| Erkrath to Radnevo | 1,085.97 mi (1,747.69 km) |
| Erkrath to Radomir | 962.13 mi (1,548.39 km) |
| Erkrath to Rakitovo | 1,030.99 mi (1,659.22 km) |
| Erkrath to Rakovski | 1,049.54 mi (1,689.08 km) |
| Erkrath to Razgrad | 1,055.11 mi (1,698.03 km) |
| Erkrath to Razlog | 1,013.30 mi (1,630.75 km) |
| Erkrath to Ruse | 1,020.60 mi (1,642.49 km) |
| Erkrath to Samokov | 994.56 mi (1,600.59 km) |
| Erkrath to Sandanski | 1,022.26 mi (1,645.17 km) |
| Erkrath to Sevlievo | 1,021.72 mi (1,644.29 km) |
| Erkrath to Shumen | 1,082.21 mi (1,741.65 km) |
| Erkrath to Silistra | 1,061.49 mi (1,708.30 km) |
| Erkrath to Sliven | 1,084.33 mi (1,745.05 km) |
