In the 1850s New York City led the nation in the manufacture and construction of cast-iron buildings. Cast-iron permitted the mass-production of such decorative features as bracketed cornices and window moldings as demonstrated in Cooper Union's Foundation building. An arcade of cast-iron arches appears on both the Third Avenue and Lafayette Place facades.
Prefabricated cast-iron was an early step in the development of the metal skeleton-supported building and in the 1850s, America's national architectural style was inspired by the architecture of Italy. Also known as Tuscan or Lombard, Italianate style is characterized by round arches, heavily decorated, bracketed cornices and eaves, tall first-floor windows, ample porches and cast-iron facades on some commercial buildings. Today, more than a century later, almost 300 cast-iron buildings are still in use in Manhattan.