| Dundalk to Opwijk | 3,814.18 mi (6,138.33 km) |
| Dundalk to Ostend | 3,756.57 mi (6,045.61 km) |
| Dundalk to Oud-Heverlee | 3,837.16 mi (6,175.31 km) |
| Dundalk to Oud-Turnhout | 3,837.49 mi (6,175.84 km) |
| Dundalk to Oudenaarde | 3,793.46 mi (6,104.98 km) |
| Dundalk to Oudenburg | 3,760.87 mi (6,052.53 km) |
| Dundalk to Oupeye | 3,879.92 mi (6,244.13 km) |
| Dundalk to Overijse | 3,833.04 mi (6,168.69 km) |
| Dundalk to Overpelt | 3,857.45 mi (6,207.97 km) |
| Dundalk to Paal | 3,852.27 mi (6,199.62 km) |
| Dundalk to Peer | 3,861.12 mi (6,213.87 km) |
| Dundalk to Pepinster | 3,890.71 mi (6,261.49 km) |
| Dundalk to Peruwelz | 3,801.15 mi (6,117.37 km) |
| Dundalk to Perwez | 3,848.59 mi (6,193.71 km) |
| Dundalk to Philippeville | 3,848.85 mi (6,194.12 km) |
