| Hard to Dixon (Illinois) | 4,539.33 mi (7,305.35 km) |
| Hard to Dobbs Ferry (New York) | 3,955.80 mi (6,366.25 km) |
| Hard to Doctor Phillips (Florida) | 4,849.70 mi (7,804.83 km) |
| Hard to Dodge City (Kansas) | 5,130.93 mi (8,257.44 km) |
| Hard to Dolton (Illinois) | 4,477.97 mi (7,206.60 km) |
| Hard to Donna (Texas) | 5,662.51 mi (9,112.93 km) |
| Hard to Dorado (Puerto Rico) | 4,636.93 mi (7,462.41 km) |
| Hard to Doral (Florida) | 4,926.77 mi (7,928.87 km) |
| Hard to Doraville (Georgia) | 4,707.42 mi (7,575.87 km) |
| Hard to Dothan (Alabama) | 4,883.27 mi (7,858.87 km) |
| Hard to Douglas (Arizona) | 5,814.44 mi (9,357.43 km) |
| Hard to Douglas (Georgia) | 4,761.98 mi (7,663.66 km) |
| Hard to Douglasville (Georgia) | 4,733.54 mi (7,617.89 km) |
| Hard to Dover (Delaware) | 4,103.13 mi (6,603.35 km) |
| Hard to Dover (New Hampshire) | 3,743.72 mi (6,024.93 km) |
