在以下频道推出： Pluto TV
第 1 季，第 1 集: Take a trip underground and get up close and personal with titans of tunneling: the biggest, baddest tunnel boring machines on the planet. These monsters dig deeper and faster than ever before, gouging holes in the Earth's crust for subways and sewers.
Documentary · 2012年4月26日 · 43 分钟