| South Milwaukee to Octeville | 3,912.97 mi (6,297.31 km) |
| South Milwaukee to Oignies | 4,061.98 mi (6,537.12 km) |
| South Milwaukee to Oissel | 4,029.27 mi (6,484.48 km) |
| South Milwaukee to Olivet | 4,113.83 mi (6,620.56 km) |
| South Milwaukee to Ollioules | 4,454.43 mi (7,168.71 km) |
| South Milwaukee to Olonne-sur-Mer | 4,013.85 mi (6,459.66 km) |
| South Milwaukee to Oloron-Sainte-Marie | 4,183.88 mi (6,733.30 km) |
| South Milwaukee to Onet Village | 4,272.80 mi (6,876.40 km) |
| South Milwaukee to Onnaing | 4,087.64 mi (6,578.42 km) |
| South Milwaukee to Orange | 4,372.14 mi (7,036.29 km) |
| South Milwaukee to Orchies | 4,071.21 mi (6,551.98 km) |
| South Milwaukee to Orleans | 4,112.75 mi (6,618.83 km) |
| South Milwaukee to Orly | 4,101.08 mi (6,600.05 km) |
| South Milwaukee to Ormesson-sur-Marne | 4,105.20 mi (6,606.68 km) |
| South Milwaukee to Orsay | 4,094.77 mi (6,589.89 km) |
