Only part of it, I think, one building I visited Is basically the way it was when Edison used it. Almost everything is original
He rebuilt everything, starting the next day. Not a single employee was fired even when he lost a fortune and half the buildings turned to dust.
We visited 1/14/2018 (for the second time). All of the buildings open to the public are original structures and filled with artifacts found on-site. It's amazing. A ranger said they hope to get the 'factory floor' working again with a future grant.
In its day, the Laboratory complex consisted of many buildings. The fire didn't destroy them all. The buildings there today are original. A few have been repurposed and closed to the public, but most of them are open to the public and remain mostly as they were when Edison died.
It all depends what you mean by original. If Edison was anything he was into creative destruction. As something would improve, he would get rid of the old. The Edison Museum is basically frozen in Time, from his death. If you wanted to see an earlier Laboratory, I would recommend Dearborn Michigan.
Everything there is original except for some that are explicitly labeled as replicas. When we visited there end of year last year, a guide (voluntee) was talking about Edison and Tesla. He is incredibly knowledgeable about everything about Edison. According to him, the fire did not destroy all the buildings.
We visited in summer of 2017. Not sure what u mean by original, but we got to see a lot of old things. His factory looked as is. We dint know about any fire when we went and the place sure dint look burned down.
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