Exploring abandoned prisons and caverns in Japan

It is semi-panopticon, and is a design used in several Japanese prisons including some still in use. The cell areas are designed like a spoked wheel, the floor supervisor has a desk in the “hub” and can see down all of the hallways just by turning his head. However since the cells open off the hallways, you can’t see into the cells proper from the central desk. If you noticed when the camera panned up there was grating overhead? There was probably such a central desk on each floor, and the guards could look up or down to see the central rooms above and/or below them. The idea was if something started to happen on one floor the other guards on the other floors could react and lock down their prisoners before things spread. One of the news shows here recently filmed inside a prison that had this layout, and the guard guiding the reporter around was pointing out the view from the desk, although in that prison they only seemed to have 2 floors with the central desk on the second. The reporter was told when they call roll on the prisoners, for example, a guard at the entrance to each hallway will signal to the head guard at the desk that “his” hallway is OK.