Located on the ground floor of the town hall of Peñarroya de Tastavins. The building has been considerably altered but retains features of interest, including a fine window on the main upper floor and, notably, the former prison. This jail was built into the town hall, a 16th-century building that has since been profoundly transformed by subsequent reforms and remodelling. The prison complex comprises three interconnected rooms. The first is identified as the jailer's quarters, and the other two served as cells. The last cell has a narrow, confined access through a passage carved into the rock. Entry is through a door with a conopial arch on the intrados. The first room communicates with the outside through a simple square window with a sturdy iron grille. All three rooms have vaulted stone ceilings. The floor is earth and the walls are rubblework masonry. Some graffiti survives on the jambs and lintel of the doorway to the first cell. An iron shackle ring remains in the inner cell, where prisoners were chained. The access door is open; entry is free.