Cities in the United States grew so much between 1880 and 1900 because of the industrialization of society, technological advancements, elevators, steel beams, and the new arrival of millions of immigrants.
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There were several reasons why cities grew so quickly in the United States in the late 1800s. ... Many immigrants were coming to the United States during this time. Mass transit, in the form of trolleys, cable cars, and subways, was built, and skyscrapers began to dominate city skylines.