| Willoughby to Duluth (Minnesota) | 637.91 mi (1,026.61 km) |
| Willoughby to Dumas (Texas) | 1,173.99 mi (1,889.35 km) |
| Willoughby to Dumont (New Jersey) | 387.88 mi (624.24 km) |
| Willoughby to Duncan (Oklahoma) | 1,020.88 mi (1,642.95 km) |
| Willoughby to Duncanville (Texas) | 1,053.61 mi (1,695.61 km) |
| Willoughby to Dundalk (Maryland) | 306.00 mi (492.46 km) |
| Willoughby to Dunedin (Florida) | 943.77 mi (1,518.85 km) |
| Willoughby to Dunkirk (New York) | 121.08 mi (194.86 km) |
| Willoughby to Dunmore (Pennsylvania) | 300.42 mi (483.49 km) |
| Willoughby to Dunwoody (Georgia) | 555.31 mi (893.69 km) |
| Willoughby to Durango (Colorado) | 1,438.13 mi (2,314.44 km) |
| Willoughby to Durant (Oklahoma) | 971.61 mi (1,563.66 km) |
| Willoughby to Durham (North Carolina) | 414.07 mi (666.39 km) |
| Willoughby to Dyer (Indiana) | 315.44 mi (507.66 km) |
| Willoughby to Dyersburg (Tennessee) | 577.09 mi (928.74 km) |
