| Merthyr Tudful to Manor (Texas) | 4,768.05 mi (7,673.43 km) |
| Merthyr Tudful to Manorville (New York) | 3,267.04 mi (5,257.80 km) |
| Merthyr Tudful to Mansfield (Ohio) | 3,665.90 mi (5,899.69 km) |
| Merthyr Tudful to Mansfield (Texas) | 4,638.24 mi (7,464.53 km) |
| Merthyr Tudful to Manteca (California) | 5,207.34 mi (8,380.40 km) |
| Merthyr Tudful to Manville (New Jersey) | 3,354.50 mi (5,398.54 km) |
| Merthyr Tudful to Maple Grove (Minnesota) | 3,886.08 mi (6,254.04 km) |
| Merthyr Tudful to Maple Heights (Ohio) | 3,598.81 mi (5,791.72 km) |
| Merthyr Tudful to Maple Valley (Washington) | 4,689.99 mi (7,547.81 km) |
| Merthyr Tudful to Mapleton (Utah) | 4,768.45 mi (7,674.08 km) |
| Merthyr Tudful to Maplewood (Minnesota) | 3,875.89 mi (6,237.64 km) |
| Merthyr Tudful to Marana (Arizona) | 5,170.59 mi (8,321.25 km) |
| Merthyr Tudful to Marco Island (Florida) | 4,343.41 mi (6,990.05 km) |
| Merthyr Tudful to Margate (Florida) | 4,264.55 mi (6,863.13 km) |
| Merthyr Tudful to Maricopa (Arizona) | 5,167.37 mi (8,316.08 km) |
