| Gardelegen to Opwijk | 326.51 mi (525.47 km) |
| Gardelegen to Ostend | 372.19 mi (598.98 km) |
| Gardelegen to Oud-Heverlee | 310.83 mi (500.24 km) |
| Gardelegen to Oud-Turnhout | 285.50 mi (459.47 km) |
| Gardelegen to Oudenaarde | 353.09 mi (568.25 km) |
| Gardelegen to Oudenburg | 369.75 mi (595.05 km) |
| Gardelegen to Oupeye | 276.69 mi (445.29 km) |
| Gardelegen to Overijse | 317.57 mi (511.08 km) |
| Gardelegen to Overpelt | 270.41 mi (435.19 km) |
| Gardelegen to Paal | 284.91 mi (458.51 km) |
| Gardelegen to Peer | 271.16 mi (436.38 km) |
| Gardelegen to Pepinster | 275.09 mi (442.71 km) |
| Gardelegen to Peruwelz | 363.07 mi (584.31 km) |
| Gardelegen to Perwez | 311.37 mi (501.10 km) |
| Gardelegen to Philippeville | 335.92 mi (540.61 km) |
