| Merthyr Tudful to Bountiful (Utah) | 4,737.67 mi (7,624.55 km) |
| Merthyr Tudful to Bourbonnais (Illinois) | 3,857.16 mi (6,207.50 km) |
| Merthyr Tudful to Bowie (Maryland) | 3,512.39 mi (5,652.64 km) |
| Merthyr Tudful to Bowling Green (Kentucky) | 3,997.53 mi (6,433.40 km) |
| Merthyr Tudful to Bowling Green (Ohio) | 3,682.94 mi (5,927.12 km) |
| Merthyr Tudful to Box Elder (South Dakota) | 4,274.04 mi (6,878.40 km) |
| Merthyr Tudful to Boynton Beach (Florida) | 4,244.84 mi (6,831.40 km) |
| Merthyr Tudful to Bozeman (Montana) | 4,456.69 mi (7,172.35 km) |
| Merthyr Tudful to Bradenton (Florida) | 4,301.97 mi (6,923.36 km) |
| Merthyr Tudful to Bradfordville (Florida) | 4,216.59 mi (6,785.95 km) |
| Merthyr Tudful to Bradley (Illinois) | 3,856.75 mi (6,206.83 km) |
| Merthyr Tudful to Bradley Gardens (New Jersey) | 3,356.47 mi (5,401.72 km) |
| Merthyr Tudful to Brainerd (Minnesota) | 3,855.28 mi (6,204.48 km) |
| Merthyr Tudful to Brambleton (Virginia) | 3,543.76 mi (5,703.13 km) |
| Merthyr Tudful to Brandermill (Virginia) | 3,618.39 mi (5,823.23 km) |
