If today the Haras National du Pin represents a real architectural heritage, this unprecedented and innovative royal construction of equestrian architecture originally had a primarily functional vocation of accommodation for horses and renewal of the equine genetic heritage. Long improperly attributed to Jules Hardouin-Mansart and Le Nôtre, its sober decor very marked by the architecture of the school of Versailles was designed by the architects Pierre Le Mousseux and Robert de Cotte. They imagined a horseshoe plan with a set of buildings ordered around a large main courtyard.