| Portsmouth to Nuth | 303.98 mi (489.21 km) |
| Portsmouth to Oegstgeest | 257.09 mi (413.74 km) |
| Portsmouth to Oirschot | 280.84 mi (451.97 km) |
| Portsmouth to Oisterwijk | 277.39 mi (446.41 km) |
| Portsmouth to Oldebroek | 320.33 mi (515.53 km) |
| Portsmouth to Oldenzaal | 359.76 mi (578.98 km) |
| Portsmouth to Ommen | 342.45 mi (551.12 km) |
| Portsmouth to Oosterend | 340.46 mi (547.91 km) |
| Portsmouth to Oosterhout | 263.55 mi (424.15 km) |
| Portsmouth to Oosterwolde | 348.70 mi (561.18 km) |
| Portsmouth to Oostzaan | 279.61 mi (449.99 km) |
| Portsmouth to Opmeer | 289.37 mi (465.70 km) |
| Portsmouth to Oss | 292.88 mi (471.35 km) |
| Portsmouth to Oud-Beijerland | 247.00 mi (397.51 km) |
| Portsmouth to Oudenbosch | 248.83 mi (400.45 km) |
