| Harpenden to Dillenburg | 380.46 mi (612.30 km) |
| Harpenden to Dillingen | 527.98 mi (849.69 km) |
| Harpenden to Dillingen | 354.32 mi (570.22 km) |
| Harpenden to Dingolfing | 608.22 mi (978.83 km) |
| Harpenden to Dinkelsbuhl | 505.87 mi (814.11 km) |
| Harpenden to Dinklage | 363.55 mi (585.08 km) |
| Harpenden to Dinslaken | 303.85 mi (489.01 km) |
| Harpenden to Dippoldiswalde | 607.30 mi (977.36 km) |
| Harpenden to Ditzingen | 463.60 mi (746.09 km) |
| Harpenden to Dobeln | 580.73 mi (934.59 km) |
| Harpenden to Doberlug-Kirchhain | 595.08 mi (957.69 km) |
| Harpenden to Donaueschingen | 475.63 mi (765.46 km) |
| Harpenden to Donauworth | 536.95 mi (864.13 km) |
| Harpenden to Donzdorf | 498.16 mi (801.71 km) |
| Harpenden to Dorfen | 605.58 mi (974.59 km) |
