1) The Channel Tunnel linked the Britain and the rest of Europe
2) Three concrete tubes each 5 ft. thick, plunge into the earth at Coquelles, France and make passage through the English Channel.
3) The passengers can board the two trains running at a speed greater than 100mph through these tubes.
4) Passengers board not on foot, but in automobiles and buses.
5) The third tube is used basically for maintenance and emergency vehicles.
6) It is one of the intelligent structures built with immense precision. Huge pistons open and close ducts, relieving the pressure that builds ahead of the train’s noses. Some 300miles of cold water piping run alongside the rail tracks to drain off the heat raised by air friction.
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