Building Giants season 4 episode 3
Underground Mega Highway
An expert team of engineers use hi-tech explosions and state-of-the-art drilling rigs to tear through solid granite and build an 11-mile underground tunnel, one of the longest in the world.
An expert team of engineers use hi-tech explosions and state-of-the-art drilling rigs to tear through solid granite and build an 11-mile underground tunnel, one of the longest in the world.
