| Potters Bar to Oerlinghausen | 378.08 mi (608.46 km) |
| Potters Bar to Oestrich-Winkel | 375.51 mi (604.33 km) |
| Potters Bar to Offenburg | 423.11 mi (680.94 km) |
| Potters Bar to Oftersheim | 416.94 mi (671.00 km) |
| Potters Bar to Ohrdruf | 475.30 mi (764.92 km) |
| Potters Bar to Ohringen | 459.20 mi (739.01 km) |
| Potters Bar to Olbernhau | 588.86 mi (947.67 km) |
| Potters Bar to Olching | 564.69 mi (908.77 km) |
| Potters Bar to Oldenburg | 367.41 mi (591.28 km) |
| Potters Bar to Oldenburg in Holstein | 493.38 mi (794.02 km) |
| Potters Bar to Olfen | 323.81 mi (521.13 km) |
| Potters Bar to Olpe | 348.88 mi (561.47 km) |
| Potters Bar to Olsberg | 373.11 mi (600.46 km) |
| Potters Bar to Oranienburg | 571.78 mi (920.20 km) |
| Potters Bar to Ortenberg | 411.73 mi (662.62 km) |
