when were the twin towers built before 911
World Trade Center (1973–2001) In January 1967, the Port Authority awarded $74 million in contracts to various steel suppliers.[56] Construction work began on the North Tower in August 1968, and construction on the South Tower was under way by January 1969.[57] The original Hudson Tubes, which carried PATH trains into Hudson Terminal, remained in service during the construction process until 1971, when a new station opened.[58] The topping out ceremony of 1 WTC (North Tower) took place on December 23, 1970, while 2 WTC's ceremony (South Tower) occurred later on July 19, 1971.[57] The first tenants moved into the North Tower on December 15, 1970,[1] while the South Tower started accepting tenants in January 1972.[59] When the World Trade Center twin towers were completed, the total costs to the Port Authority had reached $900 million.[60] The ribbon cutting ceremony was on April 4, 1973.[61]
Red Fort It was designated a UNESCO World Heritage Site in 2007 as part of the Red Fort Complex.[2][6]
World Trade Center (1973–2001) When completed in 1972, 1 World Trade Center became the tallest building in the world for two years, surpassing the Empire State Building after a 40-year reign. The North Tower stood 1,368 feet (417 m) tall and featured a telecommunications antenna or mast that was added at the top of the roof in 1978 and stood 362 feet (110 m) tall. With the 362-foot (110 m)-tall antenna/mast, the highest point of the North Tower reached 1,730 feet (530 m).[89] Chicago's Sears Tower, finished in May 1973, reached 1,450 feet (440 m) at the rooftop.[91] Throughout their existence, the WTC towers had more floors (at 110) than any other building.[89] This number was not surpassed until the advent of the Burj Khalifa, which opened in 2010.[92][93] Each tower had a total mass of around 500,000 tons.[94]
New Covent Garden Market Construction began in 1971 on the site of the former Nine Elms Locomotive Works, and the market opened on 11 November 1974.