| Iowa City to Octeville | 4,112.07 mi (6,617.75 km) |
| Iowa City to Oignies | 4,258.38 mi (6,853.20 km) |
| Iowa City to Oissel | 4,227.63 mi (6,803.72 km) |
| Iowa City to Olivet | 4,313.28 mi (6,941.56 km) |
| Iowa City to Ollioules | 4,656.13 mi (7,493.32 km) |
| Iowa City to Olonne-sur-Mer | 4,215.70 mi (6,784.51 km) |
| Iowa City to Oloron-Sainte-Marie | 4,387.60 mi (7,061.16 km) |
| Iowa City to Onet Village | 4,474.80 mi (7,201.49 km) |
| Iowa City to Onnaing | 4,283.87 mi (6,894.22 km) |
| Iowa City to Orange | 4,573.53 mi (7,360.38 km) |
| Iowa City to Orchies | 4,267.50 mi (6,867.88 km) |
| Iowa City to Orleans | 4,312.17 mi (6,939.76 km) |
| Iowa City to Orly | 4,299.52 mi (6,919.40 km) |
| Iowa City to Ormesson-sur-Marne | 4,303.54 mi (6,925.87 km) |
| Iowa City to Orsay | 4,293.33 mi (6,909.45 km) |
