| Holyhead to Caguas (Puerto Rico) | 4,042.02 mi (6,505.01 km) |
| Holyhead to Cahokia (Illinois) | 3,978.19 mi (6,402.27 km) |
| Holyhead to Calabasas (California) | 5,223.98 mi (8,407.19 km) |
| Holyhead to Caldwell (Idaho) | 4,626.84 mi (7,446.18 km) |
| Holyhead to Caledonia (Wisconsin) | 3,688.77 mi (5,936.49 km) |
| Holyhead to Calera (Alabama) | 4,114.11 mi (6,621.01 km) |
| Holyhead to Calexico (California) | 5,201.97 mi (8,371.77 km) |
| Holyhead to Calhoun (Georgia) | 3,974.23 mi (6,395.91 km) |
| Holyhead to California (Maryland) | 3,453.94 mi (5,558.58 km) |
| Holyhead to California City (California) | 5,140.23 mi (8,272.41 km) |
| Holyhead to Callaway (Florida) | 4,217.97 mi (6,788.17 km) |
| Holyhead to Calumet City (Illinois) | 3,731.94 mi (6,005.97 km) |
| Holyhead to Calverton (Maryland) | 3,437.00 mi (5,531.31 km) |
| Holyhead to Camano (Washington) | 4,538.94 mi (7,304.72 km) |
| Holyhead to Camarillo (California) | 5,230.77 mi (8,418.12 km) |
