Рет қаралды 179,161
Eighty four years ago this month, the Holland Tunnel, linking the island of Manhattan to New Jersey under the Hudson River in the USA, opened to traffic. Two 16ft long shields, weighing 400 tons, excavated the twin tubes. On a good day, the shields, with a forward thrust of 6,000 tons, advanced 40ft. Seven years after construction began, President Calvin Coolidge pressed a golden lever that parted American flags on both sides of the tunnel at one minute after midnight November 13, 1927, to open the tunnel. In all, 496,500 yd3 of muck were excavated; 129,400 yd3 of concrete was cast; and 3.1 million ceiling tiles and 2.9 million wall tiles were installed.