| Rock Island to McHenry (Illinois) | 132.15 mi (212.67 km) |
| Rock Island to McKeesport (Pennsylvania) | 565.79 mi (910.54 km) |
| Rock Island to McKinleyville (California) | 1,730.86 mi (2,785.55 km) |
| Rock Island to McKinney (Texas) | 661.45 mi (1,064.50 km) |
| Rock Island to McLean (Virginia) | 726.90 mi (1,169.82 km) |
| Rock Island to McMinnville (Oregon) | 1,647.39 mi (2,651.21 km) |
| Rock Island to McMinnville (Tennessee) | 476.19 mi (766.36 km) |
| Rock Island to McNair (Virginia) | 715.64 mi (1,151.71 km) |
| Rock Island to McPherson (Kansas) | 431.64 mi (694.66 km) |
| Rock Island to Mead Valley (California) | 1,545.56 mi (2,487.33 km) |
| Rock Island to Meadow Woods (Florida) | 1,043.99 mi (1,680.13 km) |
| Rock Island to Meadowbrook (Virginia) | 752.04 mi (1,210.29 km) |
| Rock Island to Meadville (Pennsylvania) | 539.36 mi (868.01 km) |
| Rock Island to Mebane (North Carolina) | 712.89 mi (1,147.28 km) |
| Rock Island to Mechanicsville (Virginia) | 752.08 mi (1,210.36 km) |
