| Harpenden to Dabrowa Gornicza | 852.01 mi (1,371.17 km) |
| Harpenden to Dabrowa Tarnowska | 931.45 mi (1,499.03 km) |
| Harpenden to Darlowo | 716.06 mi (1,152.38 km) |
| Harpenden to Debica | 952.11 mi (1,532.28 km) |
| Harpenden to Deblin | 947.89 mi (1,525.48 km) |
| Harpenden to Debno | 638.31 mi (1,027.26 km) |
| Harpenden to Dobre Miasto | 874.30 mi (1,407.05 km) |
| Harpenden to Drawsko Pomorskie | 685.43 mi (1,103.10 km) |
| Harpenden to Drezdenko | 685.61 mi (1,103.39 km) |
| Harpenden to Dzialdowo | 865.75 mi (1,393.29 km) |
| Harpenden to Dzierzoniow | 737.13 mi (1,186.30 km) |
| Harpenden to Elblag | 834.46 mi (1,342.93 km) |
| Harpenden to Elk | 954.29 mi (1,535.78 km) |
| Harpenden to Garwolin | 934.62 mi (1,504.12 km) |
| Harpenden to Gdansk | 804.93 mi (1,295.41 km) |
