This is Cell Block 9 (Dan 9) which is the only prisoner block still standing. There are two floors with single cells on each floor. Apparently only one prisoner would be locked up in each cell. These days there could be 50 in one cell. At the top of each door there is a sliding locking mechanism which was operated by a guard at the end of the corridor. Each cell also had its own lock. Today these cells contain the examples of torture methods from the past.
