| Willoughby to Dover (New Hampshire) | 546.89 mi (880.14 km) |
| Willoughby to Dover (New Jersey) | 359.44 mi (578.46 km) |
| Willoughby to Dover (Ohio) | 77.17 mi (124.19 km) |
| Willoughby to Downers Grove (Illinois) | 340.90 mi (548.62 km) |
| Willoughby to Downey (California) | 2,057.70 mi (3,311.55 km) |
| Willoughby to Dranesville (Virginia) | 280.67 mi (451.69 km) |
| Willoughby to Draper (Utah) | 1,579.96 mi (2,542.71 km) |
| Willoughby to Drexel Heights (Arizona) | 1,753.49 mi (2,821.97 km) |
| Willoughby to Drexel Hill (Pennsylvania) | 340.04 mi (547.24 km) |
| Willoughby to Duarte (California) | 2,041.69 mi (3,285.79 km) |
| Willoughby to Dublin (California) | 2,150.09 mi (3,460.23 km) |
| Willoughby to Dublin (Georgia) | 634.95 mi (1,021.85 km) |
| Willoughby to Dublin (Ohio) | 139.56 mi (224.60 km) |
| Willoughby to Dubuque (Iowa) | 480.29 mi (772.95 km) |
| Willoughby to Duluth (Georgia) | 548.61 mi (882.90 km) |
