| Holyhead to Orthez | 701.04 mi (1,128.21 km) |
| Holyhead to Orvault | 437.69 mi (704.40 km) |
| Holyhead to Osny | 412.35 mi (663.61 km) |
| Holyhead to Ostwald | 628.93 mi (1,012.16 km) |
| Holyhead to Ouistreham | 336.39 mi (541.36 km) |
| Holyhead to Oullins | 673.14 mi (1,083.32 km) |
| Holyhead to Outreau | 320.04 mi (515.05 km) |
| Holyhead to Oyonnax | 668.16 mi (1,075.30 km) |
| Holyhead to Ozoir-la-Ferriere | 445.59 mi (717.11 km) |
| Holyhead to Pace | 377.81 mi (608.03 km) |
| Holyhead to Palaiseau | 435.73 mi (701.23 km) |
| Holyhead to Pamiers | 759.94 mi (1,223.01 km) |
| Holyhead to Panazol | 580.30 mi (933.90 km) |
| Holyhead to Pantin | 431.00 mi (693.63 km) |
| Holyhead to Paray-le-Monial | 612.58 mi (985.85 km) |
