City of Brooklyn in the context of "Verrazzano-Narrows Bridge"

Suburbanization (American English), also spelled suburbanisation (British English), is a population shift from historic core cities or rural areas into suburbs. Most suburbs are built in a formation of (sub)urban sprawl. As a consequence of the movement of households and businesses away from city centers, low-density, peripheral urban areas grow. Proponents of curbing suburbanization argue that sprawl leads to urban decay and a concentration of lower-income residents in the inner city, in addition to environmental harm.

Suburbanization can be a progressive process, as growing population pushes outward the zones of the concentric zone model that move outward to escape the increasing density of inward areas. For example, Kings County, New York served New York City as farmland in the 18th century, with boats carrying produce across the East River. The steam ferry later made Brooklyn Heights a commuter town for Wall Street. Streetcar suburbs spread through the county, and as elevated railways further extended its reach, the City of Brooklyn grew to fill the county. Areas along the river became industrialized and apartment buildings filled the places where factories did not replace the scattered houses. As a result, much of Brooklyn transformed into a suburban economy and later into an urban economy entirely.

The West Bronx is a region in the New York City borough of the Bronx. The region lies west of the Bronx River and roughly corresponds to the western half of the borough.

The West Bronx is more densely populated than the East Bronx, and is closer to Upper Manhattan. From the late 17th century to the middle 19th century this included the central and southern part of the Town of Yonkers, but then became the separate Town of Kingsbridge. In 1874, the then towns of Kingsbridge, West Farms and Morrisania were transferred to New York County, becoming the first area outside Manhattan to be annexed by the City of New York. Today's West Bronx was then known as the "Annexed District". In 1895, the city annexed the modern-day East Bronx, followed in 1898 by western Queens County (today's borough of Queens, with the remainder of what was eastern Queens County becoming the newly formed Nassau County), all of the City of Brooklyn (today's borough of Brooklyn), and all of Richmond County (today's borough of Staten Island) to form the consolidated city of New York.

40°40′16″N 73°59′20″W / 40.671°N 73.989°W / 40.671; -73.989

South Brooklyn is a historic term for a section of the former City of Brooklyn – now the New York City borough of Brooklyn – encompassing what are now the Boerum Hill, Carroll Gardens, Cobble Hill, Gowanus, Park Slope, Windsor Terrace, Sunset Park and Red Hook neighborhoods. It was named for its location along the waterfront that was the southern border of the original Village of Brooklyn, and has remained widely used as a colloquialism despite it no longer being the southernmost point of the borough. It should not be confused with the geographic southern region of the modern borough of Brooklyn, which includes the neighborhoods of Gravesend, Seagate, Coney Island, Brighton Beach, Manhattan Beach, Sheepshead Bay, Gerritsen Beach, Marine Park, Mill Basin, and Bergen Beach.