| Clarksburg to Octeville | 3,639.37 mi (5,856.99 km) |
| Clarksburg to Oignies | 3,811.84 mi (6,134.57 km) |
| Clarksburg to Oissel | 3,761.34 mi (6,053.29 km) |
| Clarksburg to Olivet | 3,833.68 mi (6,169.70 km) |
| Clarksburg to Ollioules | 4,144.78 mi (6,670.38 km) |
| Clarksburg to Olonne-sur-Mer | 3,708.11 mi (5,967.62 km) |
| Clarksburg to Oloron-Sainte-Marie | 3,850.30 mi (6,196.45 km) |
| Clarksburg to Onet Village | 3,961.71 mi (6,375.76 km) |
| Clarksburg to Onnaing | 3,838.64 mi (6,177.69 km) |
| Clarksburg to Orange | 4,067.35 mi (6,545.76 km) |
| Clarksburg to Orchies | 3,821.95 mi (6,150.83 km) |
| Clarksburg to Orleans | 3,833.01 mi (6,168.64 km) |
| Clarksburg to Orly | 3,831.38 mi (6,166.02 km) |
| Clarksburg to Ormesson-sur-Marne | 3,836.41 mi (6,174.11 km) |
| Clarksburg to Orsay | 3,823.92 mi (6,154.00 km) |
