| Erkrath to Smolyan | 1,073.04 mi (1,726.88 km) |
| Erkrath to Sofia | 968.98 mi (1,559.43 km) |
| Erkrath to Sopot | 1,024.69 mi (1,649.09 km) |
| Erkrath to Sozopol | 1,149.79 mi (1,850.40 km) |
| Erkrath to Sredets | 1,133.00 mi (1,823.38 km) |
| Erkrath to Stamboliyski | 1,040.55 mi (1,674.60 km) |
| Erkrath to Stara Zagora | 1,069.01 mi (1,720.41 km) |
| Erkrath to Svilengrad | 1,120.69 mi (1,803.57 km) |
| Erkrath to Svishtov | 1,005.28 mi (1,617.84 km) |
| Erkrath to Targovishte | 1,069.67 mi (1,721.47 km) |
| Erkrath to Teteven | 994.12 mi (1,599.89 km) |
| Erkrath to Troyan | 1,012.82 mi (1,629.97 km) |
| Erkrath to Tryavna | 1,043.75 mi (1,679.75 km) |
| Erkrath to Tutrakan | 1,038.01 mi (1,670.51 km) |
| Erkrath to Varna | 1,124.46 mi (1,809.64 km) |
