| Gurnee to Octeville | 3,939.73 mi (6,340.38 km) |
| Gurnee to Oignies | 4,089.91 mi (6,582.08 km) |
| Gurnee to Oissel | 4,056.37 mi (6,528.09 km) |
| Gurnee to Olivet | 4,140.39 mi (6,663.32 km) |
| Gurnee to Ollioules | 4,479.71 mi (7,209.39 km) |
| Gurnee to Olonne-sur-Mer | 4,039.07 mi (6,500.26 km) |
| Gurnee to Oloron-Sainte-Marie | 4,207.71 mi (6,771.66 km) |
| Gurnee to Onet Village | 4,297.90 mi (6,916.80 km) |
| Gurnee to Onnaing | 4,115.64 mi (6,623.48 km) |
| Gurnee to Orange | 4,397.63 mi (7,077.30 km) |
| Gurnee to Orchies | 4,099.19 mi (6,597.01 km) |
| Gurnee to Orleans | 4,139.34 mi (6,661.62 km) |
| Gurnee to Orly | 4,128.14 mi (6,643.60 km) |
| Gurnee to Ormesson-sur-Marne | 4,132.31 mi (6,650.30 km) |
| Gurnee to Orsay | 4,121.77 mi (6,633.35 km) |
