characterised by the inclusion of large keeps; the final replica keep to be built in this way was at Penrhyn between 1820 and 1840. Where there was an existing castle on a site, another response across 19th-century Europe was to attempt to improve the buildings, bringing their often chaotic historic features into line with a more integrated architectural aesthetic, in a style often termed Gothic Revivalism. There were numerous attempts to restore or rebuild keeps so as to produce this consistently Gothic style: in England, the architect Anthony Salvin was particularly prominent – as illustrated by reworking and heightening of the keep at Windsor Castle, while in France, Eugène Viollet-le-Duc reworked the keeps at castles in locations like Pierrefonds during the 1860s and 1870s, admittedly in a largely speculative fashion, since the original keep had been mostly destroyed in 1617. The Spanish Civil War and First and Second World Wars in the 20th century caused damage to many castle keeps across Europe; in particular, the famous keep at Coucy was destroyed by the German Army in 1917. By the late 20th century the conservation of castle keeps formed part of government policy across France, England, Ireland, and Spain. In the 21st century in England, most keeps are in ruins and form part of the tourism and heritage industries, rather than being used as functioning buildings – the keep of Windsor Castle being a rare exception. In Germany, large numbers of the bergfried towers were restored as functional buildings in the late 19th and early 20th centuries, often as government offices or youth hostels, or the modern conversion of tower houses, which in many cases have become modernised domestic homes. See also Tenshu, the Japanese castle keep Medieval architecture Semi-fortified Romanian culă Čardak, similar fortifications used by South Slavs Notes References Bibliography Anderson, William. (1980) Castles of Europe: From Charlemagne to the Renaissance. London: Ferndale. . Armitage, Ella S. (1912) The Early Norman Castles of the British isles. London: J. Murray. . Baldwin, John W. (1991) The Government of Philip Augustus: Foundations of French Royal Power in the Middle Ages. Berkeley, US: University of California Press. . Brindle, Steven and Brian Kerr. (1997) Windsor Revealed: New Light on the History of the Castle. London: English Heritage. . Brown, R. Allen. (1962) English Castles. London: Batsford. . Butler, Lawrence. (1997) Clifford's Tower and the Castles of York. London: English Heritage. . Châtelain,