Answer:
The expansion of the railroad made it easier for people to travel in and out of cities. The railroad also provided a faster, cheaper mode of transportation than the stagecoach, so people could expand their markets to supply people who lived in cities far from the source of production. In addition, the railroad provided jobs and sparked the growth of other industries that centered around cities at railroad hubs. People seeking jobs would filter into these areas to work. All of this contributed to urbanization.
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