The Palace of Versailles offers a visual history of French architecture from the 17th century to the end of the 18th century. It began with the original château, with the brick and stone and sloping slate mansard roofs of the Louis XIII style used by architect Philibert Le Roy. It then became grander and more monumental, with the addition of the colonnades and flat roofs of the new royal apartments in the French classical or Louis XIV style, as designed by Louis Le Vau and later Jules Hardouin-Mansart. It concluded in the lighter and more graceful neoclassical Louis XVI style of the Petit Trianon, completed by Ange-Jacques Gabriel in 1768.