| Grenaa to Oignies | 523.24 mi (842.07 km) |
| Grenaa to Oissel | 635.88 mi (1,023.34 km) |
| Grenaa to Olivet | 701.96 mi (1,129.70 km) |
| Grenaa to Ollioules | 943.91 mi (1,519.08 km) |
| Grenaa to Olonne-sur-Mer | 870.69 mi (1,401.23 km) |
| Grenaa to Oloron-Sainte-Marie | 1,044.46 mi (1,680.89 km) |
| Grenaa to Onet Village | 907.79 mi (1,460.94 km) |
| Grenaa to Onnaing | 512.98 mi (825.57 km) |
| Grenaa to Orange | 888.96 mi (1,430.64 km) |
| Grenaa to Orchies | 516.63 mi (831.43 km) |
| Grenaa to Orleans | 699.45 mi (1,125.65 km) |
| Grenaa to Orly | 637.99 mi (1,026.75 km) |
| Grenaa to Ormesson-sur-Marne | 632.13 mi (1,017.32 km) |
| Grenaa to Orsay | 645.50 mi (1,038.84 km) |
| Grenaa to Orthez | 1,029.65 mi (1,657.06 km) |
