| Irmo to Opwijk | 4,247.58 mi (6,835.82 km) |
| Irmo to Ostend | 4,189.91 mi (6,743.01 km) |
| Irmo to Oud-Heverlee | 4,270.53 mi (6,872.76 km) |
| Irmo to Oud-Turnhout | 4,271.76 mi (6,874.73 km) |
| Irmo to Oudenaarde | 4,226.43 mi (6,801.78 km) |
| Irmo to Oudenburg | 4,194.17 mi (6,749.86 km) |
| Irmo to Oupeye | 4,313.48 mi (6,941.88 km) |
| Irmo to Overijse | 4,266.28 mi (6,865.91 km) |
| Irmo to Overpelt | 4,291.73 mi (6,906.87 km) |
| Irmo to Paal | 4,286.17 mi (6,897.93 km) |
| Irmo to Peer | 4,295.28 mi (6,912.58 km) |
| Irmo to Pepinster | 4,324.12 mi (6,959.00 km) |
| Irmo to Peruwelz | 4,233.54 mi (6,813.23 km) |
| Irmo to Perwez | 4,281.68 mi (6,890.69 km) |
| Irmo to Philippeville | 4,281.10 mi (6,889.76 km) |
