The closest portion of Iowa to Colorado is near Sioux City. This is about 320 miles (515 km) from the NE corner of Colorado near Julesberg. There are no direct interstate highway routes, so the driving distance is closer from southern Iowa.
Council Bluffs, in extreme SW Iowa, is adjacent to Omaha, Nebraska. The driving distance from Omaha to the Colorado border (along I-80 / I-76 west) is about 357 miles (575 km) and to Denver is 538 miles (866 km).
per Mapquest.com --- 785 miles.
According to Google Maps, it's about 640 to 660 miles from Colorado Springs to Harlan, Iowa, depending on which route you take.
671 miles
It is 758.47 miles according to MapQuest.
It is 895 miles according to Google Maps.
It is 786 miles according to Google Maps.
Omaha is MUCH closer to Iowa than Colorado - as Omaha sits on the Missouri River, which is the dividing line between Nebraska and Iowa. Colorado is several hundred miles to the west.
It is 741.25 miles according to MapQuest.
It is 703.48 miles according to MapQuest.
It is 706.33 miles according to MapQuest.
About 71 miles.
36 miles