| Harpenden to Hoyo de Manzanares | 790.72 mi (1,272.54 km) |
| Harpenden to Huelva | 1,056.59 mi (1,700.41 km) |
| Harpenden to Huercal de Almeria | 1,036.85 mi (1,668.65 km) |
| Harpenden to Huercal-Overa | 1,000.27 mi (1,609.78 km) |
| Harpenden to Huesca | 669.12 mi (1,076.84 km) |
| Harpenden to Huetor Vega | 1,025.47 mi (1,650.34 km) |
| Harpenden to Huetor-Tajar | 1,026.26 mi (1,651.60 km) |
| Harpenden to Humanes de Madrid | 815.92 mi (1,313.10 km) |
| Harpenden to Ibi | 911.42 mi (1,466.80 km) |
| Harpenden to Ibiza | 896.03 mi (1,442.01 km) |
| Harpenden to Icod de los Vinos | 1,827.80 mi (2,941.55 km) |
| Harpenden to Igualada | 713.33 mi (1,147.99 km) |
| Harpenden to Illescas | 825.30 mi (1,328.19 km) |
| Harpenden to Inca | 850.57 mi (1,368.86 km) |
| Harpenden to Ingenio | 1,826.20 mi (2,938.98 km) |
