| Monroe to Opwijk | 4,761.94 mi (7,663.60 km) |
| Monroe to Ostend | 4,704.74 mi (7,571.56 km) |
| Monroe to Oud-Heverlee | 4,784.91 mi (7,700.56 km) |
| Monroe to Oud-Turnhout | 4,782.33 mi (7,696.42 km) |
| Monroe to Oudenaarde | 4,742.60 mi (7,632.47 km) |
| Monroe to Oudenburg | 4,709.15 mi (7,578.65 km) |
| Monroe to Oupeye | 4,826.89 mi (7,768.12 km) |
| Monroe to Overijse | 4,781.23 mi (7,694.64 km) |
| Monroe to Overpelt | 4,802.18 mi (7,728.36 km) |
| Monroe to Paal | 4,798.25 mi (7,722.04 km) |
| Monroe to Peer | 4,806.22 mi (7,734.86 km) |
| Monroe to Pepinster | 4,838.13 mi (7,786.21 km) |
| Monroe to Peruwelz | 4,751.95 mi (7,647.52 km) |
| Monroe to Perwez | 4,797.16 mi (7,720.29 km) |
| Monroe to Philippeville | 4,799.84 mi (7,724.60 km) |
