| Northolt to Oberkirch | 428.65 mi (689.85 km) |
| Northolt to Obernburg am Main | 432.32 mi (695.76 km) |
| Northolt to Obernkirchen | 407.18 mi (655.29 km) |
| Northolt to Oberschleissheim | 577.16 mi (928.85 km) |
| Northolt to Oberstdorf | 556.21 mi (895.13 km) |
| Northolt to Obertraubling | 580.96 mi (934.96 km) |
| Northolt to Obertshausen | 414.34 mi (666.81 km) |
| Northolt to Oberursel | 400.69 mi (644.84 km) |
| Northolt to Ochsenfurt | 475.64 mi (765.47 km) |
| Northolt to Ochsenhausen | 518.28 mi (834.10 km) |
| Northolt to Ochtrup | 325.53 mi (523.90 km) |
| Northolt to Odenthal | 325.29 mi (523.50 km) |
| Northolt to Oelde | 365.26 mi (587.82 km) |
| Northolt to Oelsnitz | 550.19 mi (885.45 km) |
| Northolt to Oer-Erkenschwick | 327.02 mi (526.29 km) |
