| Holyhead to Nyon | 679.32 mi (1,093.26 km) |
| Holyhead to Oberriet | 748.90 mi (1,205.24 km) |
| Holyhead to Obersiggenthal | 695.39 mi (1,119.12 km) |
| Holyhead to Oberwil | 668.10 mi (1,075.20 km) |
| Holyhead to Oberwingert | 711.20 mi (1,144.57 km) |
| Holyhead to Oftringen | 689.79 mi (1,110.11 km) |
| Holyhead to Olten | 687.68 mi (1,106.71 km) |
| Holyhead to Onex | 685.63 mi (1,103.42 km) |
| Holyhead to Opfikon | 707.60 mi (1,138.77 km) |
| Holyhead to Ostermundigen | 691.96 mi (1,113.60 km) |
| Holyhead to Payerne | 679.99 mi (1,094.34 km) |
| Holyhead to Pfaffikon | 718.32 mi (1,156.03 km) |
| Holyhead to Plan-les-Ouates | 687.02 mi (1,105.66 km) |
| Holyhead to Pratteln | 673.06 mi (1,083.18 km) |
| Holyhead to Prilly | 683.28 mi (1,099.64 km) |
