| Irmo to Oerlinghausen | 4,402.28 mi (7,084.79 km) |
| Irmo to Oestrich-Winkel | 4,428.16 mi (7,126.43 km) |
| Irmo to Offenburg | 4,467.33 mi (7,189.47 km) |
| Irmo to Oftersheim | 4,469.38 mi (7,192.77 km) |
| Irmo to Ohrdruf | 4,515.32 mi (7,266.70 km) |
| Irmo to Ohringen | 4,511.86 mi (7,261.13 km) |
| Irmo to Olbernhau | 4,622.86 mi (7,439.78 km) |
| Irmo to Olching | 4,616.17 mi (7,429.02 km) |
| Irmo to Oldenburg | 4,354.03 mi (7,007.13 km) |
| Irmo to Oldenburg in Holstein | 4,424.58 mi (7,120.68 km) |
| Irmo to Olfen | 4,358.07 mi (7,013.64 km) |
| Irmo to Olpe | 4,394.27 mi (7,071.89 km) |
| Irmo to Olsberg | 4,411.42 mi (7,099.50 km) |
| Irmo to Oranienburg | 4,556.48 mi (7,332.95 km) |
| Irmo to Ortenberg | 4,461.34 mi (7,179.84 km) |
