This room, which can be reached via a narrow staircase between the walls, was used as a prison for members of the clergy from the 17th century onwards. Today, this part of the old Palace is known as the Prison Tower.
Inside, the room is spacious and offers a certain degree of comfort; there is still a large fireplace, the toilet or latrine with a wooden lid and wide, albeit barred, windows. On the walls there are openings and embrasures that fell into disuse when structures were added to the east and north of this part of the Palace. In the past the whole room would have been plastered, but now only fragments remain, on which we can read graffiti that include the testimonies of some of the prisoners, such as this one dated 1716: "Solo soy en esta prisión por tres clavos imprimidos a mi corasón."