<P> Additional users of the superblock concept are large national or multinational corporations who constructed campuses in the late 1900s and 2000s . Examples of superblock campuses include Google in Mountain View, California; and Apple and Hewlett - Packard in San Jose, California . Another well - known commercial superblock is the World Trade Center site in New York City, where several streets of Manhattan's downtown grid were removed and de-mapped to make room for the center . </P> <P> Social and housing agencies in the U.S., Canada and the UK used the superblock model for large housing projects such as Regent Park in Toronto and Benny Farm in Montreal, Canada . In New York City, the Stuyvesant Town private market, residential development superblock takes up about 18 normal city blocks and provides a large green amenity for its residents and neighbours . It uses crescent (loop) rather than dead - ended streets inside the superblock and an extensive network of paths that provide excellent connectivity within the block and to the neighbouring areas (see drawing). </P> <P> Where the superblock is used for housing projects like Stuyvesant Town, the advantages sought are an improved separation of vehicular and pedestrian circulation, enhanced tranquility and reduced accident risk within the neighbourhood . In 2003, Vauban (a rail suburb of Freiburg, Germany) was constructed with similar goals . Its layout consists mainly of a superblock with a central pedestrian spine and a few narrow looped and dead - ended streets . The British new town of Milton Keynes is built around a grid of one - kilometre square superblocks (see drawing). </P> <P> Virtual, unplanned superblocks have emerged in many cities worldwide as the outcome of stepwise modifications to streets and traffic . Most such superblocks have occurred in European city centres where the street network originates in the medieval or earlier periods . Not only is the street pattern labyrinthine, but also numerous streets that constitute it have dimensions incapable of accommodating two crossing cars or one car and pedestrians, excluding the need for parking or emergency access . Such geometric constraints and the resulting chaotic traffic conditions, along with deteriorating air quality, forced cities to remove motorized traffic from such streets . In certain cases, such as the city of Bremen, Germany, the cumulative effect of excluding motorized traffic from a number of streets made it impossible to cross the old city centre by car . The centre, however, remains completely traversable on foot or bicycle; a condition that resembles in principle the planned superblock and incorporates its design intentions . Some cities, such as Montpellier, France expanded the exclusion of traffic from the entire old centre . </P>

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