In Ohio (not sure, this maybe outside of your range.)
Check out Hocking Hills State Park/Old Mans Cave (fishing, prolly not fly)...
Also, I just got back from and you should look at Mohican Start Park (I think there are fly fishing opportunities).
Walking and hiking are there at both of these parks. At Mohican you can also Canoe and Tube your way down the river. I've stayed at both. Both are wonderful natural places and very popular parks/camps.
The Campgrounds in Ohio are showing their age, but are generally clean and well kept.
Reservations at this time of year might be hard to come by. Hocking Hills are electric only sites, there's is a KOA nearby will full hookups. Mohican has a limited number of full hookup sites in the State Park, and several commercial RV parks nearby.
I prefer the State Campgrounds, hookups or not.
Also be aware, either of these parks have limited to no cell service depending on your carrier. I use AT$T and had no coverage *at all* at Mohican.
(I had to drive 10 miles or so to get a signal when I fell and broke my nose at the camp store, so I could find a ER and get stitched up - oops! It was a EPIC face plant!) (And, yes, I was sober!)
๐At Hocking Hills, in certain areas of the campground, if I stood on one leg and held the phone over my head, I could sometimes get a signal...
That said, Both parks are a natural wonder and worth the visit. I'll be back at Hocking Hills/Old Mans cave in October, if I can avoid more injuries!
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