Inspired by the architecture of baroque Italian villas, but executed in the French classical style, the garden front and wings were encased in white cut ashlar stone known as the "enveloppe" in 1668–1671 by Le Vau and modified by Hardouin-Mansart in 1678–1679. The exterior features an arcaded, rusticated ground floor, supporting a main floor with round-headed windows divided by reliefs and pilasters or columns. The attic storey has square windows and pilasters and crowned by a balustrade bearing sculptured trophies and flame pots dissimulating a flat roof.