| Northolt to Oerlinghausen | 387.33 mi (623.34 km) |
| Northolt to Oestrich-Winkel | 380.77 mi (612.78 km) |
| Northolt to Offenburg | 425.36 mi (684.54 km) |
| Northolt to Oftersheim | 421.27 mi (677.97 km) |
| Northolt to Ohrdruf | 482.90 mi (777.16 km) |
| Northolt to Ohringen | 463.72 mi (746.29 km) |
| Northolt to Olbernhau | 596.69 mi (960.27 km) |
| Northolt to Olching | 568.62 mi (915.11 km) |
| Northolt to Oldenburg | 378.48 mi (609.11 km) |
| Northolt to Oldenburg in Holstein | 505.18 mi (813.01 km) |
| Northolt to Olfen | 332.57 mi (535.22 km) |
| Northolt to Olpe | 356.22 mi (573.28 km) |
| Northolt to Olsberg | 381.24 mi (613.54 km) |
| Northolt to Oranienburg | 581.97 mi (936.58 km) |
| Northolt to Ortenberg | 418.12 mi (672.89 km) |
