The Swiss and many other European dignitaries celebrated the opening of the World’s longest and deepest tunnel last week, the Gotthard Base Tunnel, after 17 years of construction. The tunnel beneath the Swiss Alps is 57-kilometers long (35-miles long) reaching a depth of 2,300 meters (7,545 feet, almost 1.5 miles). The tunnel will create a high-speed rail link between northern and southern Europe. Trains will travel the tunnel, which runs between the towns of Erstfeld in the north and Bodio in the south, in only 20 minutes, reaching speeds of up to 250 kilometers an hour (155 mph), according to CNN. [Source: CNN via AGC SmartBrief. Image: Global Rail News]
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12 Miles of Tunnels for D.C. Sewer
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