| Castellon de la Plana to Smolyan | 1,294.22 mi (2,082.84 km) |
| Castellon de la Plana to Sofia | 1,222.37 mi (1,967.21 km) |
| Castellon de la Plana to Sopot | 1,294.48 mi (2,083.27 km) |
| Castellon de la Plana to Sozopol | 1,445.03 mi (2,325.56 km) |
| Castellon de la Plana to Sredets | 1,419.76 mi (2,284.88 km) |
| Castellon de la Plana to Stamboliyski | 1,284.00 mi (2,066.40 km) |
| Castellon de la Plana to Stara Zagora | 1,340.51 mi (2,157.34 km) |
| Castellon de la Plana to Svilengrad | 1,370.72 mi (2,205.95 km) |
| Castellon de la Plana to Svishtov | 1,325.86 mi (2,133.77 km) |
| Castellon de la Plana to Targovishte | 1,387.20 mi (2,232.49 km) |
| Castellon de la Plana to Teteven | 1,270.08 mi (2,044.00 km) |
| Castellon de la Plana to Troyan | 1,292.83 mi (2,080.60 km) |
| Castellon de la Plana to Tryavna | 1,332.49 mi (2,144.43 km) |
| Castellon de la Plana to Tutrakan | 1,390.13 mi (2,237.20 km) |
| Castellon de la Plana to Varna | 1,454.34 mi (2,340.53 km) |
