overall geographical region of the United States, the Rust Belt has no precise boundaries. The extent to which a community may have been described as a "Rust Belt city" depends on how great a role industrial manufacturing played in its local economy in the past and how it does now, as well as on perceptions of the economic viability and living standards of the present day. News media occasionally refer to a patchwork of defunct centers of heavy industry and manufacturing across the Great Lakes and Midwestern United States as the snow belt, the manufacturing belt, or the factory belt – because of their vibrant industrial economies in the past. This includes most of the cities of the Midwest as far west as the Mississippi River, including St. Louis, and many of those in the Great Lakes and Northern New York. At the center of this expanse lies an area stretching from northern Indiana and southern Michigan in the west to Upstate New York in the east, where local tax revenues relied more heavily on manufacturing than on any other sector. Before World War II, the cities in the Rust Belt region were among the largest in the United States. However, by the twentieth century's end their population had fallen the most in the country. History The linking of the former Northwest Territory with the once-rapidly industrializing East Coast was effected through several large-scale infrastructural projects, most notably the Erie Canal in 1825, the Baltimore and Ohio Railroad in 1830, the Allegheny Portage Railroad in 1834, and the consolidation of the New York Central after the American Civil War. A gate was thereby opened between a variety of burgeoning industries on the interior North American continent and the markets not only of the large Eastern cities but of Western Europe as well. Coal, iron ore, and other raw materials were shipped in from surrounding regions which emerged as major ports on the Great Lakes and served as transportation hubs for the region with proximity to railroad lines. Coming in the other direction were millions of European immigrants, who populated the cities along the Great Lakes shores with then-unprecedented speed. Chicago, famously, was a rural trading post in the 1840s but grew to be as big as Paris by the time of the 1893 Columbian Exposition. Early signs of the difficulty in the northern states were evident early in the 20th