Sainte-Geneviève Library

The Sainte-Geneviève Library stands as a landmark of modern architecture because it was the first major public building in France to openly display a structural iron frame. Before its construction in the mid-nineteenth century, architects typically hid metal supports behind stone or wood, viewing iron as purely industrial material fit only for factories or bridges. Architect Henri Labrouste challenged this convention by using slender, cast-iron columns to support the expansive reading room on the building's second floor. He left these iron arches exposed, allowing the structure itself to define the aesthetic of the space. This bold choice paved the way for future architects to embrace metal as a primary element of monumental design.