| Piqua to Opwijk | 4,080.94 mi (6,567.64 km) |
| Piqua to Ostend | 4,023.88 mi (6,475.82 km) |
| Piqua to Oud-Heverlee | 4,103.89 mi (6,604.57 km) |
| Piqua to Oud-Turnhout | 4,100.74 mi (6,599.51 km) |
| Piqua to Oudenaarde | 4,061.92 mi (6,537.03 km) |
| Piqua to Oudenburg | 4,028.31 mi (6,482.94 km) |
| Piqua to Oupeye | 4,145.67 mi (6,671.82 km) |
| Piqua to Overijse | 4,100.30 mi (6,598.80 km) |
| Piqua to Overpelt | 4,120.56 mi (6,631.39 km) |
| Piqua to Paal | 4,116.87 mi (6,625.46 km) |
| Piqua to Peer | 4,124.66 mi (6,638.00 km) |
| Piqua to Pepinster | 4,157.00 mi (6,690.04 km) |
| Piqua to Peruwelz | 4,071.66 mi (6,552.70 km) |
| Piqua to Perwez | 4,116.31 mi (6,624.57 km) |
| Piqua to Philippeville | 4,119.56 mi (6,629.79 km) |
