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Explosives Through Mountain
It would take nearly 2,000 gunpowder, nitroglycerin, or dynamite explosions and almost five years to blast a mile-long tunnel through this mountain.

Gunpowder _+_ Hard Rock __ Maybe
Learn more       Tunnel Score: 30

Blasting explosives like gunpowder, nitroglycerin, and dynamite all work well for carving a tunnel through a mountain. The dense rock walls can support themselves, and they won't collapse into the tunnel like loose sand or soggy soil would. But, you also need to be a fast runner, or the explosion will probably kill you. Here's why:

First, you have to whack a pipe two or three feet deep into the tunnel wall. Then you must pound the explosive into the pipe, ignite a fuse with a candle, and run as fast as you can before the mountain wall blows up. Luckily, this method was only popular 200 years ago. Today, there's an easier way to blast through a mountain -- and you don't have to be a sprinter to do it!


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