I know that there was a mental health hospital run by Illinois in East Moline when I was a kid . My grandfather went insane and died in the East Moline State Hospital. I.remember that the area was called the Quint Cities on the radio years ago.
If I am not mistaken I think even Carroll, Ogle, Whiteside, Jo Davies. And other counties in Iowa and western Illinois are considered part of the quad cities. I know that when there are storms in the forecast those counties get their weather reports from the Quad Cities weather bureau.
If you are not from the Quad Cities, you could not tell where one town ends and the next one begins. Davenport and Bettendorf are like Rockford and Loves Park Illinois. You just cross from one town to the other. Rock Island is smaller than Moline I think.
I lived in about every city here except moline or silvis. I finally settled here in bettendorf and this is where ill die. The people here are so laid back compared to the other cities here.