| Saint-Omer to Oria | 1,022.44 mi (1,645.46 km) |
| Saint-Omer to Oristano | 809.07 mi (1,302.07 km) |
| Saint-Omer to Orta Nova | 913.57 mi (1,470.25 km) |
| Saint-Omer to Orte | 746.23 mi (1,200.95 km) |
| Saint-Omer to Ortona | 816.21 mi (1,313.56 km) |
| Saint-Omer to Orvieto | 723.56 mi (1,164.46 km) |
| Saint-Omer to Orzinuovi | 511.35 mi (822.95 km) |
| Saint-Omer to Osimo | 726.81 mi (1,169.69 km) |
| Saint-Omer to Ospitaletto | 507.84 mi (817.28 km) |
| Saint-Omer to Ostuni | 1,008.60 mi (1,623.19 km) |
| Saint-Omer to Ottaviano | 899.87 mi (1,448.20 km) |
| Saint-Omer to Ovada | 515.68 mi (829.90 km) |
| Saint-Omer to Ozieri | 773.23 mi (1,244.40 km) |
| Saint-Omer to Paceco | 1,015.72 mi (1,634.64 km) |
| Saint-Omer to Pachino | 1,158.55 mi (1,864.51 km) |
