| Portsmouth to Nyon | 452.68 mi (728.52 km) |
| Portsmouth to Oberriet | 538.54 mi (866.70 km) |
| Portsmouth to Obersiggenthal | 481.46 mi (774.83 km) |
| Portsmouth to Oberwil | 451.48 mi (726.59 km) |
| Portsmouth to Oberwingert | 499.40 mi (803.70 km) |
| Portsmouth to Oftringen | 473.11 mi (761.40 km) |
| Portsmouth to Olten | 471.18 mi (758.29 km) |
| Portsmouth to Onex | 458.19 mi (737.39 km) |
| Portsmouth to Opfikon | 494.31 mi (795.52 km) |
| Portsmouth to Ostermundigen | 471.40 mi (758.64 km) |
| Portsmouth to Payerne | 456.90 mi (735.31 km) |
| Portsmouth to Pfaffikon | 505.35 mi (813.28 km) |
| Portsmouth to Plan-les-Ouates | 459.57 mi (739.61 km) |
| Portsmouth to Pratteln | 457.03 mi (735.53 km) |
| Portsmouth to Prilly | 458.03 mi (737.13 km) |
