The 95.3-mile (153.5 km) long Gotthard Base tunnel network now being drilled out beneath the Alps, when finally completed in about ten years, will be the longest underground tunnel ever constructed.

目前正在阿尔卑斯山脚开凿的圣哥达隧道网长95.3英里(153.5公里)，将在10年以后完工，也将是有史以来最长的地下隧道。

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Even on a dry day, the MTA's 300 pumping rooms remove an estimated 13 million gallons of water from the tunnel network, just to keep the system dry enough to run.

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And traffic between geographically separated company networks can be routed through a virtual private network (VPN) tunnel instead of being exposed to the open Internet.

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This loop also passes through the Sasso San Gottardo, a demilitarised tunnel that is part of a network of clandestine Swiss Army caves and tunnels built into the mountain and used as bunkers during WWII and the Cold War.

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