| Holyhead to Dardenne Prairie (Missouri) | 3,989.83 mi (6,421.02 km) |
| Holyhead to Darien (Illinois) | 3,742.07 mi (6,022.28 km) |
| Holyhead to Davenport (Iowa) | 3,849.43 mi (6,195.06 km) |
| Holyhead to Davidson (North Carolina) | 3,761.28 mi (6,053.20 km) |
| Holyhead to Davie (Florida) | 4,211.65 mi (6,777.99 km) |
| Holyhead to Davis (California) | 5,066.45 mi (8,153.66 km) |
| Holyhead to Dayton (Nevada) | 4,960.53 mi (7,983.21 km) |
| Holyhead to Dayton (Ohio) | 3,689.59 mi (5,937.82 km) |
| Holyhead to Daytona Beach (Florida) | 4,084.71 mi (6,573.70 km) |
| Holyhead to De Pere (Wisconsin) | 3,620.96 mi (5,827.38 km) |
| Holyhead to De Witt (New York) | 3,224.91 mi (5,189.99 km) |
| Holyhead to Dearborn (Michigan) | 3,534.12 mi (5,687.62 km) |
| Holyhead to Dearborn Heights (Michigan) | 3,536.41 mi (5,691.30 km) |
| Holyhead to DeBary (Florida) | 4,110.12 mi (6,614.60 km) |
| Holyhead to Decatur (Alabama) | 4,051.43 mi (6,520.15 km) |
