| On Top of the World Designated Place to Opwijk | 4,538.52 mi (7,304.04 km) |
| On Top of the World Designated Place to Ostend | 4,480.85 mi (7,211.24 km) |
| On Top of the World Designated Place to Oud-Heverlee | 4,561.36 mi (7,340.80 km) |
| On Top of the World Designated Place to Oud-Turnhout | 4,564.56 mi (7,345.96 km) |
| On Top of the World Designated Place to Oudenaarde | 4,516.49 mi (7,268.59 km) |
| On Top of the World Designated Place to Oudenburg | 4,485.01 mi (7,217.93 km) |
| On Top of the World Designated Place to Oupeye | 4,604.64 mi (7,410.44 km) |
| On Top of the World Designated Place to Overijse | 4,556.82 mi (7,333.49 km) |
| On Top of the World Designated Place to Overpelt | 4,584.51 mi (7,378.06 km) |
| On Top of the World Designated Place to Paal | 4,578.13 mi (7,367.79 km) |
| On Top of the World Designated Place to Peer | 4,587.79 mi (7,383.34 km) |
| On Top of the World Designated Place to Pepinster | 4,614.90 mi (7,426.97 km) |
| On Top of the World Designated Place to Peruwelz | 4,522.37 mi (7,278.05 km) |
| On Top of the World Designated Place to Perwez | 4,571.86 mi (7,357.70 km) |
| On Top of the World Designated Place to Philippeville | 4,569.52 mi (7,353.94 km) |
