The Louvre was conceived as a great encyclopaedic museum of world art. Its origins as a museum go back to the Age of Enlightenment, which was when the concepts of encyclopaedic knowledge were established. The palace where the museum is housed had always been a royal residence and was always open to art classes and to members of the Academy and artists who wished to contemplate its galleries. When it became a national museum it was designed to be an enormous school of art, open to artists and scholars and later in the 19th century to the general public. This educational intention influenced the Spaniards of the Enlightenment who organised the Museo del Prado's collections in Madrid. The Louvre building itself is an example of the evolutions that took place in architecture and in the fashions of art collecting in France. The Palais du Louvre, one of the largest of Europe's royal palaces, was built on the site of a medieval castle, of which the foundations and part of the moat remain today. In 1527, Francis I, king of France and a great patron of the arts, commissioned his architect, Pierre Lescot, to build a residence close to the court nucleus of Cité in Paris. The king's tastes tended towards the Italian Renaissance, the style used by Lescot to construct a classical building organised around a square patio known as the Cour Carrée. During this initial construction phase there were two other important interventions. The first was by Francis I's successor, Henry II and the second was by Henry's widow Catherine de Medicis. In 1564 Catherine commissioned Philibert de l'Orme to construct a second royal residence in the Tuileries gardens. This was the first extension that was made to the Louvre, because in 1595 both residences were linked together. A second period of remodelling took place in the 17th century. Initially in the 17th century the palace was abandoned and became a market complete with shacks leant against the walls. Later on, in the same century, Louis XIV ordered the restoration of the palace's façade. These works were done according to a strict French Baroque style which is how we see the building today. The architects were Claude Perrault, the designer of the project and a Doctor on Medicine, Le Vau and Lebrun. Construction took place between 1667 and 1670. In 1800 further transformations took place during the rule of Napoleon, who was personally responsible for instigating the works. He ordered the construction of the great triumphal arch opposite the main façade, known as the Arc du Carrousel. He also ordered various restoration programmes and the construction of the wing of the Seine, which he commissioned to the architects Percier and Fontaine. The works were finished off by his nephew, Napoleon III, who ordered the construction of the northern wing, parallel to the Seine wing, making the whole building symmetrical. Recently the Louvre has been amplified with the addition of the Grand Louvre, carried out by the architect Ieoh Ming Pei in 1995. This extension was built to give the museum greater flexibility and increase the services it offers. As a result today it has an extensive leisure area that includes restaurants, bookshops and souvenir shops, as well as projection rooms, and rooms for documentation and bibliographical information. Being an encyclopaedic museum it houses an enormous art collection, which is divided into seven thematic departments: Oriental Antiquities and Islamic art, Egyptian Antiquities, Greek, Etruscan and Roman Antiquities, objets d'art, sculpture, prints and drawings and finally its impressive collection of paintings. Apart from these thematic areas, there is another dedicated exclusively to the Louvre itself: the Medieval Louvre and the History of the Louvre. In this area the foundations and part of the moat of the original fortified castle that stood on the site can be observed. The collection was formed by each king or queen imposing his or her personal tastes on the collections and making new acquisitions up until the 19th and 20th centuries. At this time private donations and State intervention became responsible for increasing the collections and filling in their gaps.