Escher in the Palace one's eyes will be tricked by multiple interactive displays. In the rooms of the museum are fifteen chandeliers made by the Rotterdam artist, Hans van Bentem. The artist designed these especially for the museum, with some references to the work of Escher and the Palace. In the ballroom, a star chandelier is endlessly reflected in the two mirrors. In other rooms there are chandeliers such as a shark, a skull, spiders, and a sea horse. The parquet floor in the Palace was designed in 1991/92 by the American minimal artist Donald Judd on the occasion of the opening of the
Palace of Westminster rooms and bars; the first floor (known as the "principal floor") houses the main rooms of the Palace, including the debating chambers, the lobbies and the libraries. The top-two floors are used as committee rooms and offices. Some of the interiors were designed and painted by J. G. Crace, working in collaboration with Pugin and others. For example, Crace decorated and gilded the ceiling of the Chapel of St. Mary Undercroft. Instead of one main entrance, the Palace features separate entrances for the different user groups of the building. The Sovereign's Entrance, at the base of the Victoria Tower, is