Les Halles was the traditional central market of Paris. In 1183, King Philippe II Auguste enlarged the marketplace in Paris and built a shelter for the merchants, who came from all over to sell their wares. The church of Saint-Eustache was constructed in the 16th century. The circular Halle des Blés (grain exchange), designed by Nicolas Le Camus de Mézières, was built between 1763 and 1769 at the west end of Les Halles. Its circular central court was later covered with a dome, and it was converted into the Bourse de Commerce in 1889.[5] In the 1850s, Victor Baltard designed the famous glass and iron buildings, Les Halles, which would last until the 1970s. Les Halles was known as the "Belly of Paris", as it was called by Émile Zola in his novel Le Ventre de Paris, which is set in the busy marketplace of the 19th century.