An old abandoned insane asylum always makes for a good horror story setting. The US has more than a hundred abandoned asylums, so it's a trope we are all familiar with. They have quite a bit in common with each other. First, they are abandoned. Second, these old buildings all look alike. The reason for this was the influence of Pennsylvania doctor Thomas Kirkbride. He advocated for the philosophy that the mentally ill should be treated instead of simply being isolated. It was the moral thing to do.
Kirkbride worked a few years at the Friends Asylum, learning and practicing moral treatment. Then in 1840, he became superintendent of his own asylum, the Philadelphia Hospital for the Insane. It was here that he began thinking about another way to treat insanity. He started thinking a lot about the environment where patients were treated.
As part of a push to get patients out of that prison-like basement, the hospital had already commissioned a brighter, more spacious building in the countryside, but Kirkbride came to believe that even this wasn’t enough. He wanted an asylum designed with treatment in mind. A few years later, Kirkbride was given the opportunity to construct his own facility for the hospital and began to experiment. The architecture of the building, the landscaping of its grounds, the efficiency of its operation — nothing was left to chance. He documented everything he learned in an extremely detailed book called On the Construction, Organization, and General Arrangements of Hospitals for the Insane With Some Remarks on Insanity and Its Treatment.