plans to build the structure's trademark spire in secret, pushing the Chrysler Building to and making it the tallest in the world when it was completed in 1929. Both buildings were soon surpassed with the May 1931 completion of the 102-story Empire State Building with its Art Deco tower reaching at the top of the building. The high pinnacle was later added bringing the total height of the building to . The former Twin Towers of the World Trade Center were located in Lower Manhattan. At , the 110-story buildings were the world's tallest from 1972 until they were surpassed by the construction of the Willis Tower in 1974 (formerly known as the Sears Tower, located in Chicago). One World Trade Center, a replacement for the Twin Towers of the World Trade Center, is currently the tallest building in the Western Hemisphere. In 1961, the Pennsylvania Railroad unveiled plans to tear down the old Penn Station and replace it with a new Madison Square Garden and office building complex. Organized protests were aimed at preserving the McKim, Mead & White-designed structure completed in 1910, widely considered a masterpiece of the Beaux-Arts style and one of the architectural jewels of New York City. Despite these efforts, demolition of the structure began in October 1963. The loss of Penn Station—called "an act of irresponsible public vandalism" by historian Lewis Mumford—led directly to the enactment in 1965 of a local law establishing the New York City Landmarks Preservation Commission, which is responsible for preserving the "city's historic, aesthetic, and cultural heritage". The historic preservation movement triggered by Penn Station's demise has been credited with the retention of some one million structures nationwide, including over 1,000 in New York City. In 2017, a multibillion-dollar rebuilding plan was unveiled to restore the historic grandeur of Penn Station, in the process of upgrading the landmark's status as a critical transportation hub. Parkland Parkland composes 17.8% of the borough, covering a total of . The Central Park, the largest park comprising 30% of Manhattan's parkland, is bordered on the north by West 110th Street (Central Park North), on the west by Eighth Avenue (Central Park West), on the south by West 59th Street (Central Park South), and on the east by Fifth Avenue. Central Park, designed by Frederick Law Olmsted and Calvert Vaux, offers extensive walking tracks, two ice-skating rinks, a wildlife sanctuary, and several lawns and