| Duncan to Mendota Heights (Minnesota) | 757.96 mi (1,219.82 km) |
| Duncan to Menifee (California) | 1,101.82 mi (1,773.20 km) |
| Duncan to Menlo Park (California) | 1,366.34 mi (2,198.92 km) |
| Duncan to Menomonee Falls (Wisconsin) | 793.70 mi (1,277.34 km) |
| Duncan to Menomonie (Wisconsin) | 782.62 mi (1,259.50 km) |
| Duncan to Mentor (Ohio) | 1,025.49 mi (1,650.37 km) |
| Duncan to Mequon (Wisconsin) | 802.87 mi (1,292.10 km) |
| Duncan to Merced (California) | 1,273.34 mi (2,049.24 km) |
| Duncan to Mercedes (Texas) | 579.52 mi (932.65 km) |
| Duncan to Mercer Island (Washington) | 1,543.10 mi (2,483.39 km) |
| Duncan to Mercerville (New Jersey) | 1,330.09 mi (2,140.57 km) |
| Duncan to Meriden (Connecticut) | 1,444.02 mi (2,323.93 km) |
| Duncan to Meridian (Idaho) | 1,168.50 mi (1,880.52 km) |
| Duncan to Meridian (Mississippi) | 552.36 mi (888.93 km) |
| Duncan to Merriam (Kansas) | 357.20 mi (574.85 km) |
