Windsor Castle, the largest inhabited castle in the world, has been a Royal home for 900 years. Windsor was one in a series of castles; all a days ride from London, built by William the Conqueror in 1070. During its nine-century history, the castle has been attacked only twice; in 1193 when Richard the Lionheart was away on crusade and in the period prior to the signing of the Magna Carta in 1215 when barons rose up against King John.

King Henry VIII and his third queen, Jane Seymour; King Charles I, Edward VII, Henry VI, George V and Queen Mary are all buried within the walls of Windsor.

The House of Plantagenet, under the reign of Henry III (1216-1272), built Salisbury, Garter, Curfew and two other solid round towers as part of the impressive and imposing defensive wall on the southwestern part of Windsor castle. Salisbury Tower sits at the southwest comer of Windsor Castle between Garter Tower and the main entrance to the Lower Ward called Henry VIII's Gate. Salisbury Tower is now a private residence.