| Cwmbran to Oerlinghausen | 499.21 mi (803.41 km) |
| Cwmbran to Oestrich-Winkel | 493.85 mi (794.78 km) |
| Cwmbran to Offenburg | 532.75 mi (857.38 km) |
| Cwmbran to Oftersheim | 533.09 mi (857.92 km) |
| Cwmbran to Ohrdruf | 596.76 mi (960.40 km) |
| Cwmbran to Ohringen | 575.77 mi (926.61 km) |
| Cwmbran to Olbernhau | 710.43 mi (1,143.32 km) |
| Cwmbran to Olching | 679.52 mi (1,093.58 km) |
| Cwmbran to Oldenburg | 484.17 mi (779.20 km) |
| Cwmbran to Oldenburg in Holstein | 605.53 mi (974.50 km) |
| Cwmbran to Olfen | 445.33 mi (716.69 km) |
| Cwmbran to Olpe | 470.17 mi (756.66 km) |
| Cwmbran to Olsberg | 494.73 mi (796.19 km) |
| Cwmbran to Oranienburg | 691.12 mi (1,112.25 km) |
| Cwmbran to Ortenberg | 532.00 mi (856.18 km) |
