| Calne to Olympia Heights (Florida) | 4,357.52 mi (7,012.75 km) |
| Calne to Omaha (Nebraska) | 4,224.60 mi (6,798.84 km) |
| Calne to On Top of the World Designated Place (Florida) | 4,271.13 mi (6,873.73 km) |
| Calne to Onalaska (Wisconsin) | 3,920.86 mi (6,310.01 km) |
| Calne to Oneida (New York) | 3,353.42 mi (5,396.81 km) |
| Calne to Oneonta (New York) | 3,355.31 mi (5,399.84 km) |
| Calne to Ontario (California) | 5,362.63 mi (8,630.32 km) |
| Calne to Ontario (Oregon) | 4,785.04 mi (7,700.77 km) |
| Calne to Opa-locka (Florida) | 4,345.11 mi (6,992.78 km) |
| Calne to Opelika (Alabama) | 4,224.86 mi (6,799.26 km) |
| Calne to Opelousas (Louisiana) | 4,604.67 mi (7,410.50 km) |
| Calne to Orange (California) | 5,383.04 mi (8,663.17 km) |
| Calne to Orange (Texas) | 4,692.84 mi (7,552.39 km) |
| Calne to Orange City (Florida) | 4,237.52 mi (6,819.62 km) |
| Calne to Orangeburg (South Carolina) | 3,998.08 mi (6,434.28 km) |
