<Tr> <Th_colspan="2"> Listed Building--Grade II </Th> </Tr> <Tr> <Td_colspan="2"> Location of the castle in central London </Td> </Tr> <P> The Tower of London, officially Her Majesty's Royal Palace and Fortress of the Tower of London, is a historic castle located on the north bank of the River Thames in central London . It lies within the London Borough of Tower Hamlets, separated from the eastern edge of the square mile of the City of London by the open space known as Tower Hill . It was founded towards the end of 1066 as part of the Norman Conquest of England . The White Tower, which gives the entire castle its name, was built by William the Conqueror in 1078 and was a resented symbol of oppression, inflicted upon London by the new ruling elite . The castle was used as a prison from 1100 (Ranulf Flambard) until 1952 (Kray twins), although that was not its primary purpose . A grand palace early in its history, it served as a royal residence . As a whole, the Tower is a complex of several buildings set within two concentric rings of defensive walls and a moat . There were several phases of expansion, mainly under Kings Richard I, Henry III, and Edward I in the 12th and 13th centuries . The general layout established by the late 13th century remains despite later activity on the site . </P> <P> The Tower of London has played a prominent role in English history . It was besieged several times, and controlling it has been important to controlling the country . The Tower has served variously as an armoury, a treasury, a menagerie, the home of the Royal Mint, a public record office, and the home of the Crown Jewels of England . From the early 14th century until the reign of Charles II, a procession would be led from the Tower to Westminster Abbey on the coronation of a monarch . In the absence of the monarch, the Constable of the Tower is in charge of the castle . This was a powerful and trusted position in the medieval period . In the late 15th century, the castle was the prison of the Princes in the Tower . Under the Tudors, the Tower became used less as a royal residence, and despite attempts to refortify and repair the castle, its defences lagged behind developments to deal with artillery . </P>

What type of castle was the tower of london
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