| Port Huron to Opwijk | 3,880.97 mi (6,245.81 km) |
| Port Huron to Ostend | 3,824.14 mi (6,154.36 km) |
| Port Huron to Oud-Heverlee | 3,903.87 mi (6,282.67 km) |
| Port Huron to Oud-Turnhout | 3,899.85 mi (6,276.19 km) |
| Port Huron to Oudenaarde | 3,862.42 mi (6,215.97 km) |
| Port Huron to Oudenburg | 3,828.60 mi (6,161.53 km) |
| Port Huron to Oupeye | 3,945.34 mi (6,349.42 km) |
| Port Huron to Overijse | 3,900.43 mi (6,277.14 km) |
| Port Huron to Overpelt | 3,919.59 mi (6,307.97 km) |
| Port Huron to Paal | 3,916.29 mi (6,302.66 km) |
| Port Huron to Peer | 3,923.80 mi (6,314.75 km) |
| Port Huron to Pepinster | 3,956.79 mi (6,367.83 km) |
| Port Huron to Peruwelz | 3,872.69 mi (6,232.50 km) |
| Port Huron to Perwez | 3,916.54 mi (6,303.06 km) |
| Port Huron to Philippeville | 3,920.58 mi (6,309.56 km) |
