| Watford to Carmona | 1,012.99 mi (1,630.25 km) |
| Watford to Cartagena | 971.53 mi (1,563.52 km) |
| Watford to Cartama | 1,053.15 mi (1,694.88 km) |
| Watford to Cartaya | 1,046.23 mi (1,683.75 km) |
| Watford to Caspe | 720.27 mi (1,159.17 km) |
| Watford to Cassa de la Selva | 692.07 mi (1,113.78 km) |
| Watford to Castalla | 902.34 mi (1,452.17 km) |
| Watford to Castellbisbal | 712.16 mi (1,146.12 km) |
| Watford to Castelldefels | 725.57 mi (1,167.70 km) |
| Watford to Castello de Ampurias | 669.36 mi (1,077.24 km) |
| Watford to Castellon de la Plana | 806.64 mi (1,298.16 km) |
| Watford to Castilleja de la Cuesta | 1,023.89 mi (1,647.79 km) |
| Watford to Catarroja | 846.55 mi (1,362.38 km) |
| Watford to Catral | 932.67 mi (1,500.98 km) |
| Watford to Caudete | 895.26 mi (1,440.78 km) |
