Washington Square Park is 6.7 times larger than Grand Army Plaza (Manhattan).
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Grand Army Plaza lies at the intersection of Central Park South and Fifth Avenue in front of the Plaza Hotel in Manhattan, New York City. It stretches from 60th to 58th streets between East Drive and Fifth Avenue. The idea for such a plaza was first proposed by sculptor Karl Bitter in 1898. Wikipedia
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Washington Square Park is one of the best-known of New York City's 1,900 public parks. At 9.75 acres, it is a landmark in the Manhattan neighborhood of Greenwich Village, as well as a meeting place and center for cultural activity. Wikipedia