| Difficult Run to Des Plaines (Illinois) | 594.97 mi (957.51 km) |
| Difficult Run to Desert Hot Springs (California) | 2,188.63 mi (3,522.25 km) |
| Difficult Run to DeSoto (Texas) | 1,174.80 mi (1,890.66 km) |
| Difficult Run to Destin (Florida) | 782.92 mi (1,259.98 km) |
| Difficult Run to Destrehan (Louisiana) | 963.63 mi (1,550.81 km) |
| Difficult Run to Detroit (Michigan) | 385.74 mi (620.79 km) |
| Difficult Run to Diamond Bar (California) | 2,255.87 mi (3,630.47 km) |
| Difficult Run to Diamond Springs (California) | 2,319.26 mi (3,732.49 km) |
| Difficult Run to Dickinson (North Dakota) | 1,393.28 mi (2,242.27 km) |
| Difficult Run to Dickinson (Texas) | 1,201.20 mi (1,933.14 km) |
| Difficult Run to Dickson (Tennessee) | 582.90 mi (938.09 km) |
| Difficult Run to Dinuba (California) | 2,283.59 mi (3,675.08 km) |
| Difficult Run to Discovery Bay (California) | 2,373.15 mi (3,819.22 km) |
| Difficult Run to Dix Hills (New York) | 249.95 mi (402.26 km) |
| Difficult Run to Dixon (California) | 2,375.07 mi (3,822.31 km) |
