Our family went there in 2010.
One thing I noticed different from the pictures I'd seen was the roadways had all been "paved" and the edges had curbs.
I mentioned it to the docents and they indicated it was a "liability" thing.
"Our clientele is tending to be older and a lot of them were having trouble getting around the village with their canes, walkers, and wheelchairs - hence the thought that paved roadways would help improve their access."
Methinks we're seeing the ADA (American Disabilities Act) here. Soon to come an elevator to the second floor of Edison's Laboratory?
Newall post of stairs to the right.
Joe K