| Watford to Orthez | 564.55 mi (908.55 km) |
| Watford to Orvault | 307.81 mi (495.38 km) |
| Watford to Osny | 209.52 mi (337.19 km) |
| Watford to Ostwald | 418.15 mi (672.95 km) |
| Watford to Ouistreham | 164.26 mi (264.36 km) |
| Watford to Oullins | 473.84 mi (762.57 km) |
| Watford to Outreau | 108.37 mi (174.40 km) |
| Watford to Oyonnax | 462.83 mi (744.85 km) |
| Watford to Ozoir-la-Ferriere | 240.79 mi (387.52 km) |
| Watford to Pace | 249.95 mi (402.26 km) |
| Watford to Palaiseau | 234.34 mi (377.14 km) |
| Watford to Pamiers | 597.32 mi (961.29 km) |
| Watford to Panazol | 409.27 mi (658.65 km) |
| Watford to Pantin | 227.08 mi (365.45 km) |
| Watford to Paray-le-Monial | 413.43 mi (665.35 km) |
