Thanks to the renewed interest in the Middle Ages in the 19th Century, the Saint-Chapel was restored from 1841 to 1867. In a little over 2 years of construction, the architect Pierre de Montreuil brought the Gothic style to its highest summit : the arc thrusts are supported on the outside by pointed buttresses (balanced by pinnacles, but deliberately without flying buttresses) which allowed the walls to be eliminated in favor of very large stained-glass windows. The stone is particularly solid as it was cut with the grain of the quarry. Despite the frail appearance of the framework's pillars, the balance is such that there has not been a single crack in seven centuries. The decoration on the facade of the entry dates from the 19th century. Particularly interesting are the two superimposed porches. Up above, the great rose is topped by a balustrade carved with fleurs-de-lis, the symbols of royal power.