| Willoughby to Marrero (Louisiana) | 946.52 mi (1,523.28 km) |
| Willoughby to Marshall (Minnesota) | 750.42 mi (1,207.68 km) |
| Willoughby to Marshall (Missouri) | 644.25 mi (1,036.81 km) |
| Willoughby to Marshall (Texas) | 949.35 mi (1,527.82 km) |
| Willoughby to Marshalltown (Iowa) | 592.04 mi (952.80 km) |
| Willoughby to Marshfield (Wisconsin) | 488.12 mi (785.56 km) |
| Willoughby to Martha Lake (Washington) | 2,023.83 mi (3,257.05 km) |
| Willoughby to Martin (Tennessee) | 542.03 mi (872.32 km) |
| Willoughby to Martinez (California) | 2,154.70 mi (3,467.66 km) |
| Willoughby to Martinez (Georgia) | 562.65 mi (905.49 km) |
| Willoughby to Martinsburg (West Virginia) | 235.10 mi (378.35 km) |
| Willoughby to Martinsville (Indiana) | 305.45 mi (491.58 km) |
| Willoughby to Martinsville (New Jersey) | 362.77 mi (583.83 km) |
| Willoughby to Martinsville (Virginia) | 352.76 mi (567.71 km) |
| Willoughby to Maryland City (Maryland) | 299.29 mi (481.66 km) |
