Royal Botanical Garden Pavilion (1774-1781) in Madrid, Spain was designed by Juan de Villanueva (Madrid, 1739- 1811). Villanueva is the best known architect of the Spanish Neoclassicism. In 1777, Charles III appointed him Architect of the Prince and the Infants. He then almost exclusively worked for the Royal House. In 1781 he was appointed Architect of the Royal Monastery of El Escorial, and Charles IV appointed him Major Architect. His best known masterpieces include the Prado Museum (1785), Astronomical Observatory, Madrid (1790), and Reconstruction of the Plaza Mayor, Madrid (1791).