| Lake Oswego to Orbetello | 5,737.10 mi (9,232.97 km) |
| Lake Oswego to Oria | 6,013.95 mi (9,678.52 km) |
| Lake Oswego to Oristano | 5,815.76 mi (9,359.57 km) |
| Lake Oswego to Orta Nova | 5,916.97 mi (9,522.44 km) |
| Lake Oswego to Orte | 5,766.02 mi (9,279.52 km) |
| Lake Oswego to Ortona | 5,822.97 mi (9,371.17 km) |
| Lake Oswego to Orvieto | 5,743.57 mi (9,243.38 km) |
| Lake Oswego to Orzinuovi | 5,529.09 mi (8,898.21 km) |
| Lake Oswego to Osimo | 5,732.00 mi (9,224.76 km) |
| Lake Oswego to Ospitaletto | 5,523.50 mi (8,889.22 km) |
| Lake Oswego to Ostuni | 5,998.37 mi (9,653.44 km) |
| Lake Oswego to Ottaviano | 5,915.85 mi (9,520.63 km) |
| Lake Oswego to Ovada | 5,540.39 mi (8,916.39 km) |
| Lake Oswego to Ozieri | 5,787.42 mi (9,313.95 km) |
| Lake Oswego to Paceco | 6,038.81 mi (9,718.52 km) |
