| Willoughby to Decatur (Alabama) | 574.93 mi (925.26 km) |
| Willoughby to Decatur (Georgia) | 566.43 mi (911.59 km) |
| Willoughby to Decatur (Illinois) | 412.71 mi (664.20 km) |
| Willoughby to Deer Park (New York) | 424.62 mi (683.35 km) |
| Willoughby to Deer Park (Texas) | 1,126.02 mi (1,812.16 km) |
| Willoughby to Deerfield (Illinois) | 333.18 mi (536.20 km) |
| Willoughby to Deerfield Beach (Florida) | 1,062.45 mi (1,709.86 km) |
| Willoughby to Defiance (Ohio) | 155.17 mi (249.72 km) |
| Willoughby to DeForest (Wisconsin) | 418.96 mi (674.25 km) |
| Willoughby to DeKalb (Illinois) | 378.51 mi (609.16 km) |
| Willoughby to Del Aire (California) | 2,070.63 mi (3,332.35 km) |
| Willoughby to Del City (Oklahoma) | 964.31 mi (1,551.91 km) |
| Willoughby to Del Rio (Texas) | 1,379.55 mi (2,220.17 km) |
| Willoughby to DeLand (Florida) | 872.22 mi (1,403.70 km) |
| Willoughby to Delano (California) | 2,063.92 mi (3,321.56 km) |
