| Watford to Nyon | 471.72 mi (759.16 km) |
| Watford to Oberriet | 537.61 mi (865.21 km) |
| Watford to Obersiggenthal | 483.70 mi (778.44 km) |
| Watford to Oberwil | 456.41 mi (734.53 km) |
| Watford to Oberwingert | 499.69 mi (804.17 km) |
| Watford to Oftringen | 478.10 mi (769.42 km) |
| Watford to Olten | 475.98 mi (766.01 km) |
| Watford to Onex | 479.09 mi (771.02 km) |
| Watford to Opfikon | 495.95 mi (798.15 km) |
| Watford to Ostermundigen | 480.80 mi (773.78 km) |
| Watford to Payerne | 469.75 mi (755.99 km) |
| Watford to Pfaffikon | 506.70 mi (815.46 km) |
| Watford to Plan-les-Ouates | 480.49 mi (773.27 km) |
| Watford to Pratteln | 461.35 mi (742.46 km) |
| Watford to Prilly | 474.34 mi (763.38 km) |
