| Harpenden to Orthez | 575.83 mi (926.71 km) |
| Harpenden to Orvault | 319.19 mi (513.69 km) |
| Harpenden to Osny | 218.18 mi (351.12 km) |
| Harpenden to Ostwald | 421.87 mi (678.93 km) |
| Harpenden to Ouistreham | 175.43 mi (282.32 km) |
| Harpenden to Oullins | 482.43 mi (776.40 km) |
| Harpenden to Outreau | 114.02 mi (183.49 km) |
| Harpenden to Oyonnax | 470.51 mi (757.22 km) |
| Harpenden to Ozoir-la-Ferriere | 248.98 mi (400.70 km) |
| Harpenden to Pace | 261.28 mi (420.50 km) |
| Harpenden to Palaiseau | 243.13 mi (391.29 km) |
| Harpenden to Pamiers | 608.08 mi (978.61 km) |
| Harpenden to Panazol | 419.91 mi (675.79 km) |
| Harpenden to Pantin | 235.48 mi (378.96 km) |
| Harpenden to Paray-le-Monial | 422.12 mi (679.34 km) |
