| Potomac to Mexborough | 3,578.38 mi (5,758.85 km) |
| Potomac to Mickleover | 3,579.50 mi (5,760.66 km) |
| Potomac to Middlesbrough | 3,559.65 mi (5,728.70 km) |
| Potomac to Middleton | 3,541.64 mi (5,699.72 km) |
| Potomac to Middlewich | 3,538.34 mi (5,694.41 km) |
| Potomac to Midsomer Norton | 3,574.47 mi (5,752.55 km) |
| Potomac to Mildenhall | 3,673.52 mi (5,911.96 km) |
| Potomac to Milford Haven | 3,460.41 mi (5,568.99 km) |
| Potomac to Mill Hill | 3,659.58 mi (5,889.52 km) |
| Potomac to Milngavie | 3,419.21 mi (5,502.69 km) |
| Potomac to Milnrow | 3,543.60 mi (5,702.87 km) |
| Potomac to Milton | 3,553.05 mi (5,718.08 km) |
| Potomac to Milton Keynes | 3,629.02 mi (5,840.34 km) |
| Potomac to Minehead | 3,535.07 mi (5,689.15 km) |
| Potomac to Minster | 3,706.29 mi (5,964.70 km) |
