Bayley Seton Hospital was constructed in 1830's as a retreat for retired naval and sailors. They then sold it to a catholic health care organization in 1880. It when then renamed after the organizations founder Elizabeth Seton and Richard Bayley. The hospital was used mainly to treat mental disorders and substance abuse, which it still does today. In the 1930's, Roosevelt started a campaign to rejuvenate Public health hospitals, which funded the construction of 7 new buildings on the land. In the 2000's the land was sold again to another Catholic health care center, and half the hospitals services were suspended and the hospital started to decline in bankruptcy with a debt of a billion dollars. The main hospital building remains open but lots of buildings were left abandoned. Some left abandoned were, nurses residences, pysch wards, children wards and a dentistry part of the building. The buildings are on 20 acres of land, and 8 out of 12 are abandoned. The salvation army now owns the buildings and are trying to renovate them. Bayley Setons main building also inspired the Arkham Asylum in the Batman movies.
Haven't been there in a while so this might have changed. All the buildings were very easily accessible, there is security, but they watched me go into the buildings and didn't say anything. There are so many buildings you should be able to get into one. I would definitely recommend checking it out.