| Hard to Dumas (Texas) | 5,300.63 mi (8,530.54 km) |
| Hard to Dumont (New Jersey) | 3,963.72 mi (6,378.99 km) |
| Hard to Duncan (Oklahoma) | 5,219.94 mi (8,400.68 km) |
| Hard to Duncanville (Texas) | 5,278.99 mi (8,495.72 km) |
| Hard to Dundalk (Maryland) | 4,139.12 mi (6,661.28 km) |
| Hard to Dunedin (Florida) | 4,926.09 mi (7,927.78 km) |
| Hard to Dunkirk (New York) | 4,116.62 mi (6,625.06 km) |
| Hard to Dunmore (Pennsylvania) | 4,010.86 mi (6,454.86 km) |
| Hard to Dunwoody (Georgia) | 4,707.50 mi (7,575.98 km) |
| Hard to Durango (Colorado) | 5,431.47 mi (8,741.11 km) |
| Hard to Durant (Oklahoma) | 5,189.62 mi (8,351.89 km) |
| Hard to Durham (North Carolina) | 4,386.07 mi (7,058.70 km) |
| Hard to Dyer (Indiana) | 4,480.63 mi (7,210.88 km) |
| Hard to Dyersburg (Tennessee) | 4,812.73 mi (7,745.34 km) |
| Hard to Eagan (Minnesota) | 4,533.23 mi (7,295.53 km) |
