Royal residence - Windsor Castle is an official residence of The HM Queen Elizabeth II and the largest occupied castle in the world. A royal palace and fortress for over 900 years, the Castle remains a working palace today. Visitors can walk around the State Apartments, extensive suites of rooms at the heart of the working palace; for part of the year visitors can also see the Semi State rooms, which are some of the most splendid interiors in the castle. They are furnished with treasures from the Royal Collection including paintings by Holbein, Rubens, Van Dyck and Lawrence, fine tapestries and porcelain, sculpture and armour.