| Iowa City to Olympia Heights (Florida) | 1,272.41 mi (2,047.74 km) |
| Iowa City to Omaha (Nebraska) | 235.72 mi (379.36 km) |
| Iowa City to On Top of the World Designated Place (Florida) | 1,010.02 mi (1,625.47 km) |
| Iowa City to Onalaska (Wisconsin) | 155.11 mi (249.63 km) |
| Iowa City to Oneida (New York) | 814.75 mi (1,311.21 km) |
| Iowa City to Oneonta (New York) | 845.09 mi (1,360.03 km) |
| Iowa City to Ontario (California) | 1,509.74 mi (2,429.69 km) |
| Iowa City to Ontario (Oregon) | 1,294.26 mi (2,082.92 km) |
| Iowa City to Opa-locka (Florida) | 1,264.05 mi (2,034.29 km) |
| Iowa City to Opelika (Alabama) | 707.36 mi (1,138.38 km) |
| Iowa City to Opelousas (Louisiana) | 769.67 mi (1,238.66 km) |
| Iowa City to Orange (California) | 1,528.32 mi (2,459.60 km) |
| Iowa City to Orange (Texas) | 806.51 mi (1,297.95 km) |
| Iowa City to Orange City (Florida) | 1,049.96 mi (1,689.74 km) |
| Iowa City to Orangeburg (South Carolina) | 810.62 mi (1,304.57 km) |
