| Harpenden to Ponteland | 230.46 mi (370.89 km) |
| Harpenden to Pontneddfechan | 138.34 mi (222.63 km) |
| Harpenden to Pontypridd | 128.85 mi (207.36 km) |
| Harpenden to Poole | 103.71 mi (166.90 km) |
| Harpenden to Port Glasgow | 334.70 mi (538.65 km) |
| Harpenden to Port Talbot | 148.38 mi (238.79 km) |
| Harpenden to Portchester | 75.11 mi (120.87 km) |
| Harpenden to Porthcawl | 144.96 mi (233.29 km) |
| Harpenden to Portishead | 105.86 mi (170.36 km) |
| Harpenden to Portlethen | 369.23 mi (594.22 km) |
| Harpenden to Portsmouth | 76.77 mi (123.55 km) |
| Harpenden to Potters Bar | 10.98 mi (17.68 km) |
| Harpenden to Poulton le Fylde | 178.39 mi (287.09 km) |
| Harpenden to Poynton | 129.21 mi (207.94 km) |
| Harpenden to Prescot | 151.59 mi (243.97 km) |
