Nottingham Castle is a castle in Nottingham, England. It is located in a commanding position on a natural promontory known as "Castle Rock", with cliffs 130ft high to the south and west. In the Middle Ages it was a major royal fortress and occasional royal residence. In decline by the 16th century, it was largely demolished in 1649. The Duke of Newcastle later built a mansion on the site, which was burnt down by rioters in 1831 and left as a ruin. It was later rebuilt to house an art gallery and museum, which remain in use to this day. Little of the original castle survives, but sufficient portions remain to give an impression of the layout of the site.Medieval historyThere is some uncertainty whether a castle existed on the site before the Norman Conquest. If there was it would have been smaller and far less elaborate in design than the one that stood there afterwards, keeping in line with Anglo-Saxon architectural tradition.The first Norman castle was a wooden structure and of a motte-and-bailey design, and was built in 1067, the year after the Battle of Hastings, on the orders of William the Conqueror. This wooden structure was replaced by a far more defensible stone castle during the reign of King Henry II, and was imposing and of a complex architectural design, which eventually comprised an upper bailey at the highest point of the castle rock, a middle bailey to the north which contained the main royal apartments, and a large outer bailey to the east.