As I walked around the property of The New Frontier on closing day, I paid attention to a seemingly unused area, not far from the rear entrance.
The area had an outdoor courtyard, which appears to have been once surrounded by a brick wall. Part of that wall seems to have been replaced by cinder blocks. An old fancy metal door exists at one end.
I have posted a photo which shows the location of that metal door (see blue arrow), in relation to the normal rear entrance of The Frontier.
I don't know anything about this area, and once again am putting out the call to anyone who may know what this area was.