| Harpenden to Leigh-on-Sea | 47.10 mi (75.79 km) |
| Harpenden to Leighton Buzzard | 14.86 mi (23.92 km) |
| Harpenden to Leith | 309.57 mi (498.20 km) |
| Harpenden to Lemington | 225.14 mi (362.33 km) |
| Harpenden to Leominster | 105.34 mi (169.52 km) |
| Harpenden to Lerwick | 576.87 mi (928.38 km) |
| Harpenden to Letchworth | 12.26 mi (19.72 km) |
| Harpenden to Leven | 320.86 mi (516.37 km) |
| Harpenden to Lewes | 67.01 mi (107.84 km) |
| Harpenden to Leyland | 162.42 mi (261.39 km) |
| Harpenden to Leyton | 22.39 mi (36.03 km) |
| Harpenden to Lichfield | 86.42 mi (139.08 km) |
| Harpenden to Lincoln | 97.79 mi (157.38 km) |
| Harpenden to Linlithgow | 316.57 mi (509.47 km) |
| Harpenden to Linslade | 15.71 mi (25.28 km) |
