I had not really heard of it until I got away from larger cities such as Iowa City or Des Moines. Yet in almost all the small towns I go thru, I am asked that question.
The Ragbrai is an annual tour across Iowa and in most towns, this is the only occasion to see a bike rider; 10,000 to be more precise. At the same time, as I get to the western side of Iowa, on road 92, you can ride 35 km (24 mi) admiring the large open and hilly landscape and not going thru a town.
From time to time, the main road crosses dirt road; a pickup truck is easily visible in the distance by the dust it raises on its way. You can also come across with a house, most likely a farm.
Even some birds do not seem to be used to seeing cyclists around. From time to time, one of them flies right above me, screaming rather than singing as if it was warning the other birds of something strange on the road.
* The Bike league
* Bike Iowa