The World's Columbian Exposition, Chicago

Chicago hosted the World's Columbian Exposition in 1893, commemorating the 400th anniversary of Columbus's arrival in the Americas, its monumental "White City" of temporary neoclassical exhibition palaces master-planned by Daniel Burnham and landscape architect Frederick Law Olmsted around a formal court of honor and lagoon. The exposition's scale, roughly 27 million visitors over six months, and its uniform, Beaux-Arts-derived classical architecture launched the City Beautiful movement in American urban planning and set back the emerging, more radical Chicago School commercial style in prestige terms for years, even as Chicago School architects including Louis Sullivan contributed individual buildings to the fair. Its influence on American civic architecture, world's fair design, and city planning persisted for decades after its buildings, never intended to be permanent, were destroyed.