The park has been there for quite a while. I don't see why they wouldn't allow metal detecting. there used to be, quite a number of years ago, across the street from the park, a hotel. There might be things there.
The Pavilion at Keystone Beach was built mid-1920s so people have been coming to that area for quite sometime.
The Geneva Jungle at Keystone beach was built in the late 1990's. I'm pretty sure it was 1997-1998 because I was pregnant when they built it.
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