| Williamsport to Orbetello | 4,318.12 mi (6,949.35 km) |
| Williamsport to Oria | 4,668.57 mi (7,513.34 km) |
| Williamsport to Oristano | 4,295.44 mi (6,912.84 km) |
| Williamsport to Orta Nova | 4,553.50 mi (7,328.15 km) |
| Williamsport to Orte | 4,367.90 mi (7,029.45 km) |
| Williamsport to Ortona | 4,458.11 mi (7,174.64 km) |
| Williamsport to Orvieto | 4,346.49 mi (6,995.00 km) |
| Williamsport to Orzinuovi | 4,158.01 mi (6,691.66 km) |
| Williamsport to Osimo | 4,376.44 mi (7,043.21 km) |
| Williamsport to Ospitaletto | 4,158.50 mi (6,692.46 km) |
| Williamsport to Ostuni | 4,657.02 mi (7,494.76 km) |
| Williamsport to Ottaviano | 4,519.29 mi (7,273.10 km) |
| Williamsport to Ovada | 4,129.76 mi (6,646.20 km) |
| Williamsport to Ozieri | 4,289.03 mi (6,902.52 km) |
| Williamsport to Paceco | 4,546.12 mi (7,316.28 km) |
