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In the early 1850s, New York City's gridiron street system was continuing its northward expansion up Manhattan Island, unrelieved by open space reservations. Only two relatively small open spaces, Union Square and Washington Square, served Manhattan -- at a time when urban residential densities were becoming acute due to arrival of the first of many massive waves of European immigrants.
Based on a state authorization in 1856, a large area centered east/west on Manhattan Island and located beyond the northern edge of development was purchased to provide a great public "Central Park." The plan for the park, by Frederick Law Olmsted, Sr., and Calvert Vaux, designated the park as a "greensward," a district of the city intended to remain perpetually rural. In creating this planned reserve, the first large scale "natural" park in America, Olmsted and Vaux provided the model for hundreds of city parks to follow. The success of these parks also led to the creation of public park systems and their administrative park boards, board which laid the foundation for future city planning boards.
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