Windsor Castle is an official residence of The Queen and the largest occupied castle in the world. A royal palace and fortress for over 900 years, the Castle remains a working palace today. Over 900 years ago William the Conqueror, with the help of his victorious armies, commenced construction of the castle. The imposing towers and battlements of the Castle loom large from every approach to the town, creating one of the world's most spectacular skylines. No other royal residence has played such an important role in the nation's history. it is said that Windsor is home to at least five royal ghosts including King Henry VIII, Queen Elizabeth I, King Charles I and King George III (mad King George). Henry is supposed to haunt the cloisters near the Deanery with ghostly groans and the sound of dragging footsteps. The ghost of Queen Elizabeth I was seen by Lieutenant Glynn of the Grenadier Guards while he was reading in the library. He first heard the tap, tap, tap of high heels on bare boards, then the figure of Elizabeth came into view - passing so close that he could almost touch her. She entered an inner room from which there was no other exit but, although Lieutenant Glynn followed immediately, the lady vanished. The library is also said to harbour the ghost of George III. The Long Walk is said to be haunted by a young guardsman who shot himself because, according to legend, he had seen the ghost of Herne the Hunter.