| Merthyr Tudful to Dendermonde | 325.99 mi (524.63 km) |
| Merthyr Tudful to Dessel | 366.95 mi (590.54 km) |
| Merthyr Tudful to Destelbergen | 312.99 mi (503.70 km) |
| Merthyr Tudful to Deurne | 339.08 mi (545.70 km) |
| Merthyr Tudful to Diepenbeek | 383.88 mi (617.80 km) |
| Merthyr Tudful to Diest | 367.19 mi (590.93 km) |
| Merthyr Tudful to Diksmuide | 273.59 mi (440.30 km) |
| Merthyr Tudful to Dilbeek | 335.39 mi (539.76 km) |
| Merthyr Tudful to Dinant | 374.54 mi (602.77 km) |
| Merthyr Tudful to Dison | 406.90 mi (654.85 km) |
| Merthyr Tudful to Dour | 324.24 mi (521.82 km) |
| Merthyr Tudful to Drongen | 307.32 mi (494.58 km) |
| Merthyr Tudful to Duffel | 342.86 mi (551.79 km) |
| Merthyr Tudful to Durbuy | 395.31 mi (636.19 km) |
| Merthyr Tudful to Ecaussinnes-Lalaing | 337.44 mi (543.05 km) |
