The Treasury Tower
Built against the southern rampart of the Middle Castle, the Treasury Tower was constructed by Henry II Plantagenet to house his royal treasure, which consisted mainly of charters and documents.
Today the tower still houses three vaulted rooms topped by a terrace. The central room is lit by two small windows on the south side. It may have been used as a guard room or office and must have been filled with chests and cabinets. It is flanked by two small side rooms equipped with arrow slits to defend the tower in case of siege.