| Calumet City to Octeville | 3,957.81 mi (6,369.47 km) |
| Calumet City to Oignies | 4,110.35 mi (6,614.97 km) |
| Calumet City to Oissel | 4,075.11 mi (6,558.26 km) |
| Calumet City to Olivet | 4,158.06 mi (6,691.75 km) |
| Calumet City to Ollioules | 4,494.78 mi (7,233.66 km) |
| Calumet City to Olonne-sur-Mer | 4,054.12 mi (6,524.48 km) |
| Calumet City to Oloron-Sainte-Marie | 4,220.08 mi (6,791.56 km) |
| Calumet City to Onet Village | 4,312.66 mi (6,940.56 km) |
| Calumet City to Onnaing | 4,136.21 mi (6,656.58 km) |
| Calumet City to Orange | 4,413.12 mi (7,102.24 km) |
| Calumet City to Orchies | 4,119.72 mi (6,630.05 km) |
| Calumet City to Orleans | 4,157.04 mi (6,690.11 km) |
| Calumet City to Orly | 4,146.79 mi (6,673.62 km) |
| Calumet City to Ormesson-sur-Marne | 4,151.05 mi (6,680.46 km) |
| Calumet City to Orsay | 4,140.31 mi (6,663.18 km) |
