| Castrop-Rauxel to Smolyan | 1,070.43 mi (1,722.70 km) |
| Castrop-Rauxel to Sofia | 966.22 mi (1,554.98 km) |
| Castrop-Rauxel to Sopot | 1,020.59 mi (1,642.48 km) |
| Castrop-Rauxel to Sozopol | 1,143.43 mi (1,840.17 km) |
| Castrop-Rauxel to Sredets | 1,127.13 mi (1,813.94 km) |
| Castrop-Rauxel to Stamboliyski | 1,037.38 mi (1,669.49 km) |
| Castrop-Rauxel to Stara Zagora | 1,064.38 mi (1,712.95 km) |
| Castrop-Rauxel to Svilengrad | 1,116.44 mi (1,796.74 km) |
| Castrop-Rauxel to Svishtov | 999.21 mi (1,608.07 km) |
| Castrop-Rauxel to Targovishte | 1,063.09 mi (1,710.87 km) |
| Castrop-Rauxel to Teteven | 990.10 mi (1,593.41 km) |
| Castrop-Rauxel to Troyan | 1,008.41 mi (1,622.88 km) |
| Castrop-Rauxel to Tryavna | 1,038.64 mi (1,671.53 km) |
| Castrop-Rauxel to Tutrakan | 1,030.23 mi (1,658.00 km) |
| Castrop-Rauxel to Varna | 1,116.87 mi (1,797.42 km) |
