| Willoughby to Dixon (California) | 2,129.52 mi (3,427.13 km) |
| Willoughby to Dixon (Illinois) | 416.15 mi (669.72 km) |
| Willoughby to Dobbs Ferry (New York) | 393.45 mi (633.19 km) |
| Willoughby to Doctor Phillips (Florida) | 911.94 mi (1,467.63 km) |
| Willoughby to Dodge City (Kansas) | 1,022.74 mi (1,645.93 km) |
| Willoughby to Dolton (Illinois) | 319.55 mi (514.26 km) |
| Willoughby to Donna (Texas) | 1,429.40 mi (2,300.39 km) |
| Willoughby to Dorado (Puerto Rico) | 1,833.20 mi (2,950.25 km) |
| Willoughby to Doral (Florida) | 1,095.44 mi (1,762.94 km) |
| Willoughby to Doraville (Georgia) | 556.98 mi (896.37 km) |
| Willoughby to Dothan (Alabama) | 752.73 mi (1,211.40 km) |
| Willoughby to Douglas (Arizona) | 1,706.19 mi (2,745.84 km) |
| Willoughby to Douglas (Georgia) | 705.11 mi (1,134.77 km) |
| Willoughby to Douglasville (Georgia) | 575.20 mi (925.69 km) |
| Willoughby to Dover (Delaware) | 354.08 mi (569.84 km) |
