| Northglenn to Opwijk | 4,845.80 mi (7,798.55 km) |
| Northglenn to Ostend | 4,791.97 mi (7,711.93 km) |
| Northglenn to Oud-Heverlee | 4,867.88 mi (7,834.10 km) |
| Northglenn to Oud-Turnhout | 4,856.95 mi (7,816.50 km) |
| Northglenn to Oudenaarde | 4,831.29 mi (7,775.21 km) |
| Northglenn to Oudenburg | 4,796.53 mi (7,719.27 km) |
| Northglenn to Oupeye | 4,906.01 mi (7,895.47 km) |
| Northglenn to Overijse | 4,865.63 mi (7,830.48 km) |
| Northglenn to Overpelt | 4,875.72 mi (7,846.72 km) |
| Northglenn to Paal | 4,875.58 mi (7,846.49 km) |
| Northglenn to Peer | 4,880.69 mi (7,854.72 km) |
| Northglenn to Pepinster | 4,918.16 mi (7,915.01 km) |
| Northglenn to Peruwelz | 4,845.32 mi (7,797.79 km) |
| Northglenn to Perwez | 4,882.14 mi (7,857.05 km) |
| Northglenn to Philippeville | 4,892.08 mi (7,873.04 km) |
