Barrel Roof- Shady Glen Picnic Grove- PA

I’m not sure what this was, but it struck me as peculiar so I took some pictures of it. It’s now being used as a picnic shelter, but appears to have had a previous life. My first thought was salvaged roof from an old barrel roof diner, but I’m not sure. The roof itself looks quite a bit older than the poles its on or the footers, and I can’t imagine the amount of custom fabrication it seems went into this being originally done for a picnic pavilion which could have just as easily been wood and shingles.

So what do you think?
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