| Glen Ellyn to Octeville | 3,966.87 mi (6,384.06 km) |
| Glen Ellyn to Oignies | 4,118.06 mi (6,627.37 km) |
| Glen Ellyn to Oissel | 4,083.80 mi (6,572.24 km) |
| Glen Ellyn to Olivet | 4,167.37 mi (6,706.73 km) |
| Glen Ellyn to Ollioules | 4,505.55 mi (7,250.99 km) |
| Glen Ellyn to Olonne-sur-Mer | 4,064.89 mi (6,541.81 km) |
| Glen Ellyn to Oloron-Sainte-Marie | 4,232.31 mi (6,811.24 km) |
| Glen Ellyn to Onet Village | 4,323.60 mi (6,958.16 km) |
| Glen Ellyn to Onnaing | 4,143.83 mi (6,668.86 km) |
| Glen Ellyn to Orange | 4,423.66 mi (7,119.19 km) |
| Glen Ellyn to Orchies | 4,127.37 mi (6,642.36 km) |
| Glen Ellyn to Orleans | 4,166.33 mi (6,705.06 km) |
| Glen Ellyn to Orly | 4,155.54 mi (6,687.69 km) |
| Glen Ellyn to Ormesson-sur-Marne | 4,159.74 mi (6,694.45 km) |
| Glen Ellyn to Orsay | 4,149.12 mi (6,677.36 km) |
