| Iowa City to Orbetello | 4,900.07 mi (7,885.91 km) |
| Iowa City to Oria | 5,237.88 mi (8,429.55 km) |
| Iowa City to Oristano | 4,905.20 mi (7,894.16 km) |
| Iowa City to Orta Nova | 5,125.21 mi (8,248.23 km) |
| Iowa City to Orte | 4,945.09 mi (7,958.35 km) |
| Iowa City to Ortona | 5,027.97 mi (8,091.74 km) |
| Iowa City to Orvieto | 4,922.88 mi (7,922.61 km) |
| Iowa City to Orzinuovi | 4,722.31 mi (7,599.82 km) |
| Iowa City to Osimo | 4,941.67 mi (7,952.86 km) |
| Iowa City to Ospitaletto | 4,721.04 mi (7,597.78 km) |
| Iowa City to Ostuni | 5,224.92 mi (8,408.70 km) |
| Iowa City to Ottaviano | 5,099.52 mi (8,206.89 km) |
| Iowa City to Ovada | 4,704.85 mi (7,571.72 km) |
| Iowa City to Ozieri | 4,892.60 mi (7,873.88 km) |
| Iowa City to Paceco | 5,153.43 mi (8,293.65 km) |
