Apositive effect of urbanization was the building of which public transportation systems? taxis trolleys buses trains

During the 19th century, American people travelled from one city to another by rail or canal. However, as cities grew faster, transportation infrastructure  developed so as to allow citizens travel within the city much more easily than before. Before the 1880s, the most common means of transport within cities was the horse-drawn carriage known as omnibus. But, this form of transportation was an ongoing problem since horses needed to stop for taking a rest and be fed.

A positive effect of urbanization was the building of the electric trolley which was a public transportation system that ran throughout the day and night. However, as cities became larger and crowds continued to grow, the trolley lines started to be built above the streets, creating elevated trains, or L-trains.

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