High Quality Content by WIKIPEDIA articles! Windsor Castle is a medieval castle and royal residence in Windsor in the English county of Berkshire, notable for its long association with the British royal family and its architecture. The original castle was built after the Norman invasion by William the Conqueror. Since the time of Henry I it has been used by a succession of monarchs and is the longest-occupied palace in Europe. The castle`s lavish, early 19th-century State Apartments are architecturally significant, described by art historian Hugh Roberts as "a superb and unrivalled sequence of rooms widely regarded as the finest and most complete expression of later Georgian taste". The castle includes the 15th-century St George`s Chapel, considered by historian John Robinson to be "one of the supreme achievements of English Perpendicular Gothic" design. More than five hundred people live and work in Windsor, making it the largest inhabited castle in the world.