Built by Mansart in the 17C, the high rooftops of the Maisons-Laffitte Castle are visible down the length of Avenue Albine, the traditional royal entrance. The interior (largely remodelled in the 18C by the Comte d'Artois, who also established the nearby racecourse) is a mix of neo-Classicism and classic Mansart style. Don't miss the Cabinet aux Miroirs and its exquisite inlaid parquet floor.