| Mullingar to Oerlinghausen | 676.50 mi (1,088.73 km) |
| Mullingar to Oestrich-Winkel | 697.91 mi (1,123.18 km) |
| Mullingar to Offenburg | 748.24 mi (1,204.18 km) |
| Mullingar to Oftersheim | 741.20 mi (1,192.85 km) |
| Mullingar to Ohrdruf | 785.64 mi (1,264.37 km) |
| Mullingar to Ohringen | 783.03 mi (1,260.17 km) |
| Mullingar to Olbernhau | 895.93 mi (1,441.86 km) |
| Mullingar to Olching | 889.36 mi (1,431.28 km) |
| Mullingar to Oldenburg | 640.92 mi (1,031.46 km) |
| Mullingar to Oldenburg in Holstein | 741.44 mi (1,193.23 km) |
| Mullingar to Olfen | 628.77 mi (1,011.91 km) |
| Mullingar to Olpe | 662.98 mi (1,066.96 km) |
| Mullingar to Olsberg | 681.58 mi (1,096.90 km) |
| Mullingar to Oranienburg | 851.45 mi (1,370.28 km) |
| Mullingar to Ortenberg | 729.84 mi (1,174.57 km) |
