Antiques.

 
I see that the word of my city is that word from of old, 
Because I see that world nested in nests of water-bays, superb, 
Rich, hemm'd thick all around with sailships and steamships, an island 
  sixteen miles long, solid-founded, 
Numberless crowded streets, high growths of iron, slender, strong, 
  light, splendidly uprising toward clear skies.... 
City of hurried and sparkling waters! city of spires and masts! 
City nested in bays! my city! 
Walt Whitman, "Mannahatta," Leaves of Grass, 1891-1892 
(final "authorized" or "deathbed" edition) 

Like Whitman's poem, nineteenth-century New York was a city of extremes and excess. For Whitman it was a city of "spires and masts," of "numberless crowded streets," and "high growths of iron." In these words he defined the characteristics of New York's landscape that became those of the modern city everywhere.

Until the middle of the nineteenth century, almost all American cities were compact, limited by how far one could walk. They were focused on harbors or riverfronts, since water transport fueled commerce. Business buildings clustered by the docks, and churches, hotels, and shops were built nearby. Residential buildings and craftsmen's shops formed an outer ring. Later in the century heavy industry began to move in around the railroad connections on the outskirts of the city.

Just as walking limited the horizontal span of the early city, technological limitations restricted the height of the buildings. Only after the 1850s was the elevator invented, and iron, rather than masonry, used for structural support. And it was not until the 1880s that the first skyscrapers began to rise. In New York, bridges and steam ferries allowed the city to expand beyond Manhattan, with the result that by 1860 Brooklyn was the third most populous city in the United States, ...