| Merthyr Tudful to Bonhill | 296.92 mi (477.85 km) |
| Merthyr Tudful to Bonnyrigg | 285.69 mi (459.78 km) |
| Merthyr Tudful to Bootle | 118.77 mi (191.14 km) |
| Merthyr Tudful to Borehamwood | 133.11 mi (214.22 km) |
| Merthyr Tudful to Boscombe | 96.82 mi (155.81 km) |
| Merthyr Tudful to Boston | 165.19 mi (265.84 km) |
| Merthyr Tudful to Bottesford | 168.79 mi (271.64 km) |
| Merthyr Tudful to Bourne | 145.33 mi (233.88 km) |
| Merthyr Tudful to Bournemouth | 95.89 mi (154.33 km) |
| Merthyr Tudful to Bournville | 77.48 mi (124.69 km) |
| Merthyr Tudful to Bovingdon | 121.58 mi (195.67 km) |
| Merthyr Tudful to Bowdon | 120.57 mi (194.04 km) |
| Merthyr Tudful to Boxley | 171.26 mi (275.62 km) |
| Merthyr Tudful to Brackley | 97.21 mi (156.44 km) |
| Merthyr Tudful to Bracknell | 115.11 mi (185.26 km) |
