| Merthyr Tudful to Lydney | 36.36 mi (58.52 km) |
| Merthyr Tudful to Lye | 72.91 mi (117.34 km) |
| Merthyr Tudful to Lymington | 104.67 mi (168.46 km) |
| Merthyr Tudful to Lymm | 119.52 mi (192.34 km) |
| Merthyr Tudful to Mablethorpe | 188.57 mi (303.47 km) |
| Merthyr Tudful to Macclesfield | 116.60 mi (187.66 km) |
| Merthyr Tudful to Mackworth | 112.86 mi (181.63 km) |
| Merthyr Tudful to Madeley | 73.26 mi (117.90 km) |
| Merthyr Tudful to Maesteg | 14.84 mi (23.88 km) |
| Merthyr Tudful to Maghull | 123.94 mi (199.46 km) |
| Merthyr Tudful to Maidenhead | 115.10 mi (185.24 km) |
| Merthyr Tudful to Maidstone | 171.12 mi (275.39 km) |
| Merthyr Tudful to Maldon | 173.43 mi (279.11 km) |
| Merthyr Tudful to Maltby | 147.65 mi (237.62 km) |
| Merthyr Tudful to Manchester | 129.04 mi (207.67 km) |
