| Merthyr Tudful to Ukiah (California) | 5,190.10 mi (8,352.66 km) |
| Merthyr Tudful to Union (Missouri) | 4,107.26 mi (6,609.99 km) |
| Merthyr Tudful to Union City (California) | 5,242.53 mi (8,437.04 km) |
| Merthyr Tudful to Union City (Georgia) | 4,083.51 mi (6,571.78 km) |
| Merthyr Tudful to Union City (New Jersey) | 3,321.94 mi (5,346.15 km) |
| Merthyr Tudful to Union City (Tennessee) | 4,127.78 mi (6,643.03 km) |
| Merthyr Tudful to Union Hill-Novelty Hill (Washington) | 4,672.26 mi (7,519.27 km) |
| Merthyr Tudful to Union Park (Florida) | 4,191.78 mi (6,746.01 km) |
| Merthyr Tudful to Uniondale (New York) | 3,306.08 mi (5,320.62 km) |
| Merthyr Tudful to Universal City (Texas) | 4,840.79 mi (7,790.50 km) |
| Merthyr Tudful to University (Florida) | 4,266.58 mi (6,866.40 km) |
| Merthyr Tudful to University City (Missouri) | 4,070.70 mi (6,551.16 km) |
| Merthyr Tudful to University Heights (Ohio) | 3,593.94 mi (5,783.88 km) |
| Merthyr Tudful to University of California-Santa Barbara (California) | 5,356.30 mi (8,620.13 km) |
| Merthyr Tudful to University Park (Texas) | 4,611.04 mi (7,420.75 km) |
