It's a whole new world down there if we can conquer its challenges. Some of the greatest human minds have been engaged in making the underground safe and accessible. In this program we look at the most breathtaking feats of technology, past and present. From pick-axed tunnels to an excavated mountain, from Roman sewers to a vast 27km long particle accelerator - these are the ways we've harnessed the potential of this, the planet's last frontier.
Episode #103 / Length: 54 minutes