| Portalegre to Oberkirch | 996.94 mi (1,604.42 km) |
| Portalegre to Obernburg am Main | 1,087.71 mi (1,750.51 km) |
| Portalegre to Obernkirchen | 1,192.28 mi (1,918.79 km) |
| Portalegre to Oberschleissheim | 1,125.57 mi (1,811.43 km) |
| Portalegre to Oberstdorf | 1,046.43 mi (1,684.06 km) |
| Portalegre to Obertraubling | 1,172.32 mi (1,886.67 km) |
| Portalegre to Obertshausen | 1,085.95 mi (1,747.66 km) |
| Portalegre to Oberursel | 1,082.66 mi (1,742.38 km) |
| Portalegre to Ochsenfurt | 1,114.37 mi (1,793.41 km) |
| Portalegre to Ochsenhausen | 1,053.69 mi (1,695.75 km) |
| Portalegre to Ochtrup | 1,130.80 mi (1,819.84 km) |
| Portalegre to Odenthal | 1,071.46 mi (1,724.35 km) |
| Portalegre to Oelde | 1,141.75 mi (1,837.48 km) |
| Portalegre to Oelsnitz | 1,221.45 mi (1,965.74 km) |
| Portalegre to Oer-Erkenschwick | 1,104.88 mi (1,778.12 km) |
