| Watford to Cadiz | 1,084.07 mi (1,744.64 km) |
| Watford to Calafell | 728.31 mi (1,172.10 km) |
| Watford to Calahorra | 650.55 mi (1,046.97 km) |
| Watford to Calasparra | 929.69 mi (1,496.19 km) |
| Watford to Calatayud | 714.41 mi (1,149.73 km) |
| Watford to Caldas de Montbuy | 702.94 mi (1,131.28 km) |
| Watford to Caldas de Reyes | 734.69 mi (1,182.37 km) |
| Watford to Calella | 708.43 mi (1,140.10 km) |
| Watford to Callosa de Segura | 935.30 mi (1,505.22 km) |
| Watford to Calpe | 899.15 mi (1,447.05 km) |
| Watford to Calvia | 846.81 mi (1,362.80 km) |
| Watford to Camas | 1,022.41 mi (1,645.41 km) |
| Watford to Cambados | 744.89 mi (1,198.78 km) |
| Watford to Cambre | 686.15 mi (1,104.25 km) |
| Watford to Cambrils | 734.79 mi (1,182.53 km) |
