| Merthyr Tudful to Bonita (California) | 5,361.78 mi (8,628.95 km) |
| Merthyr Tudful to Bonita Springs (Florida) | 4,325.72 mi (6,961.58 km) |
| Merthyr Tudful to Bonney Lake (Washington) | 4,704.11 mi (7,570.53 km) |
| Merthyr Tudful to Boone (Iowa) | 4,044.43 mi (6,508.89 km) |
| Merthyr Tudful to Boone (North Carolina) | 3,840.01 mi (6,179.90 km) |
| Merthyr Tudful to Borger (Texas) | 4,642.90 mi (7,472.03 km) |
| Merthyr Tudful to Bossier City (Louisiana) | 4,504.51 mi (7,249.31 km) |
| Merthyr Tudful to Boston (Massachusetts) | 3,135.78 mi (5,046.55 km) |
| Merthyr Tudful to Bostonia (California) | 5,350.38 mi (8,610.60 km) |
| Merthyr Tudful to Bothell (Washington) | 4,671.76 mi (7,518.48 km) |
| Merthyr Tudful to Bothell East (Washington) | 4,669.38 mi (7,514.64 km) |
| Merthyr Tudful to Bothell West (Washington) | 4,670.94 mi (7,517.15 km) |
| Merthyr Tudful to Boulder (Colorado) | 4,557.12 mi (7,333.97 km) |
| Merthyr Tudful to Boulder City (Nevada) | 5,113.75 mi (8,229.78 km) |
| Merthyr Tudful to Bound Brook (New Jersey) | 3,351.30 mi (5,393.40 km) |
