My history isn't what it should be, but Ohio does have a very rich tradition with amusement parks. I think the problem has a lot to do with over-saturation. We've got a lot of major parks with major attractions here.
There are other issues as well. Idora is, to some degree, symbolic of the economic decline of Youngstown. With big steel moving out, that area's economy was destroyed. Amusement parks are a luxury, not a necessity.
Chippewa Lake Park is just odd, but I think a part of its death was related to the construction of I-71. Before the freeway was built, people took US 42 from Cleveland to Columbus to Cincinnati. It was the only route to get you "efficiently" across the state. Of course, it took a long time, and there was time to stop and look around. To this day there are a lot of closed hotels and old restaurants along the entire route. Beyond that, the interstates could also get you quickly to Cedar Point, and the relatively new Kings Island in a decent amount of time.
Other parks, like Euclid Beach and Purtias Hill, I think just fell on hard times, and there's almost nothing left of them. That's one for my parents. The old Coney Island near Cinci, grand to see if you can find the photos, was apparently prone to flooding.
Here's a link to some of the other parks' history:
http://www.dnr.state.oh.us/ODNR/Parks/magazine/sprsum2000/amusement.htm -------------
Jeff
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