A streetcar suburb is a residential community whose growth and development was strongly shaped by the use of streetcar lines as a primary means of transportation. Such suburbs developed in the United States in the years before the automobile, when the introduction of the electric trolley or streetcar allowed the nation’s burgeoning middle class to move beyond the central city’s borders. Early suburbs were served by horsecars, but by the late 19th century cable cars and electric streetcars, or trams, were used, allowing residences to be built farther away from the urban core of a city. Streetcar suburbs, usually called additions or extensions at the time, were the forerunner of today's suburbs in the United States and Canada. San Francisco's Western Addition is one of the best examples of streetcar suburbs before westward and southward expansion occurred. Although most closely associated with the electric streetcar, the term can be used for any suburb originally built with streetcar-based transit in mind, thus some streetcar suburbs date from the early 19th century. As such, the term is general and one development called a streetcar suburb may vary greatly from others. However, some concepts are generally present in streetcar suburbs, such as straight (often gridiron) street plans and relatively narrow lots. Similar terms Railroad suburbs By 1830, many New York City area commuters were going to work in Manhattan from what are now the boroughs of Brooklyn and Queens, which were not part of New York City at that time. They commuted by ferries. In 1852, architect Alexander Jackson Davis designed Llewellyn Park in New Jersey, a planned suburb served by both ferry and steam railroad. In the 1840s and 1850s, new railroad lines fostered the development of such New York City suburbs as Yonkers, White Plains, and New Rochelle. The steam locomotive in the mid 19th century provided the wealthy with the means to live in bucolic surroundings, to socialize in country clubs and still commute to work downtown. These suburbs were what historian Kenneth T. Jackson called the "railroad suburbs" and historian Robert Fishman called a "bourgeois utopia". Outside of Philadelphia, suburbs like Radnor, Bryn Mawr, and Villanova developed along the Philadelphia Main Line. As early as 1850, 83 commuter stations had been built within a 15-mile radius of Boston. Chicago saw huge developments, with 11 separate lines serving over 100 communities by 1873. A famous community served was Riverside, Illinois,