El Escorial

The Casita del Príncipe (Spanish for 'Cottage of the Prince') is an eighteenth-century building located in San Lorenzo de El Escorial, Spain. It was designed by the neoclassical architect Juan de Villanueva for the private use of the heir to the Spanish throne Charles, Prince of Asturias, and his wife Maria Luisa. It was constructed in the 1770s and extended in the 1780s.
The word casita is the diminutive of the Spanish word for "house". The building was designed without bedrooms, as its owners slept in the palace which had been built two centuries earlier for Philip II. Such buildings gave their royal occupants the opportunity to escape some of the formalities of court life. The Petit Trianon at Versailles offers a French example of the phenomenon.