| Rhondda to Morristown (New Jersey) | 3,339.83 mi (5,374.94 km) |
| Rhondda to Morristown (Tennessee) | 3,908.13 mi (6,289.53 km) |
| Rhondda to Morrisville (North Carolina) | 3,741.35 mi (6,021.12 km) |
| Rhondda to Morro Bay (California) | 5,338.39 mi (8,591.31 km) |
| Rhondda to Morton (Illinois) | 3,947.30 mi (6,352.57 km) |
| Rhondda to Morton Grove (Illinois) | 3,816.59 mi (6,142.21 km) |
| Rhondda to Moscow (Idaho) | 4,587.12 mi (7,382.26 km) |
| Rhondda to Moses Lake (Washington) | 4,631.45 mi (7,453.59 km) |
| Rhondda to Moss Bluff (Louisiana) | 4,600.03 mi (7,403.03 km) |
| Rhondda to Moss Point (Mississippi) | 4,403.43 mi (7,086.64 km) |
| Rhondda to Moultrie (Georgia) | 4,170.13 mi (6,711.17 km) |
| Rhondda to Mounds View (Minnesota) | 3,880.08 mi (6,244.39 km) |
| Rhondda to Mount Airy (North Carolina) | 3,783.85 mi (6,089.51 km) |
| Rhondda to Mount Clemens (Michigan) | 3,600.53 mi (5,794.50 km) |
| Rhondda to Mount Dora (Florida) | 4,196.15 mi (6,753.06 km) |
