| Watford to Caldicot | 101.05 mi (162.62 km) |
| Watford to Calne | 70.75 mi (113.87 km) |
| Watford to Cam | 84.39 mi (135.82 km) |
| Watford to Camberley | 26.66 mi (42.90 km) |
| Watford to Camborne | 235.59 mi (379.14 km) |
| Watford to Cambridge | 43.90 mi (70.64 km) |
| Watford to Cambuslang | 326.28 mi (525.09 km) |
| Watford to Canford Cliffs | 93.65 mi (150.71 km) |
| Watford to Cannock | 99.50 mi (160.14 km) |
| Watford to Canterbury | 68.60 mi (110.40 km) |
| Watford to Carlisle | 247.10 mi (397.66 km) |
| Watford to Carlton Colville | 104.43 mi (168.07 km) |
| Watford to Carluke | 314.89 mi (506.77 km) |
| Watford to Carnoustie | 347.67 mi (559.52 km) |
| Watford to Carshalton | 22.30 mi (35.88 km) |
