The Victoria Tower incorporates a cast-iron framework which, rather than the visible stonework, provides the main strength supporting the structure. When the wrought-iron flagstaff was erected, the tower became the tallest square tower in the world, at to the base of the flagstaff, and a further to the top of the crown finial at its summit. In 1897, the King's Tower was officially renamed as the "Victoria Tower" in tribute to Queen Victoria in her Diamond Jubilee year. The Parliamentary Archives underwent a complete reconstruction between 1948 and 1963 to provide 12 floors of air-conditioned document storage, and again between 2000 and 2004 to bring it up to contemporary archive storage standards. The records are preserved by cleaning, flattening and repairing old documents. New parchment was created for the Acts whose skins was torn. Some were pasted on linen and then covered with silk gauze to protect them. Gallery References Buildings and structures in the City of Westminster National government buildings in London Gothic Revival architecture in London Government buildings completed in 1860 Palace of Westminster Towers completed in 1860 Towers in London 1860 establishments in England