| Holyhead to Oxford (Alabama) | 4,055.67 mi (6,526.97 km) |
| Holyhead to Oxford (Mississippi) | 4,161.86 mi (6,697.86 km) |
| Holyhead to Oxford (Ohio) | 3,723.69 mi (5,992.70 km) |
| Holyhead to Oxnard (California) | 5,237.08 mi (8,428.27 km) |
| Holyhead to Oxon Hill (Maryland) | 3,450.37 mi (5,552.84 km) |
| Holyhead to Ozark (Alabama) | 4,154.73 mi (6,686.40 km) |
| Holyhead to Ozark (Missouri) | 4,169.41 mi (6,710.02 km) |
| Holyhead to Pace (Florida) | 4,257.93 mi (6,852.48 km) |
| Holyhead to Pacific Grove (California) | 5,183.69 mi (8,342.34 km) |
| Holyhead to Pacifica (California) | 5,143.08 mi (8,276.99 km) |
| Holyhead to Paducah (Kentucky) | 3,992.49 mi (6,425.28 km) |
| Holyhead to Pahrump (Nevada) | 5,019.42 mi (8,077.98 km) |
| Holyhead to Painesville (Ohio) | 3,485.15 mi (5,608.80 km) |
| Holyhead to Palatine (Illinois) | 3,726.83 mi (5,997.75 km) |
| Holyhead to Palatka (Florida) | 4,085.19 mi (6,574.48 km) |
