One of the world's largest cruise ship, "Symphony of the Seas". Inside overview: how they work, how the world's largest ship engines are assembled for an ocean liner, and how these engines work, how many sheets need to be ironed and how many dishes to wash in one day of the cruise, who needs on board tons of ice, does it all harm the environment, why is there a 19th century telephone on an ultra-modern ship. And will there be enough lifeboats for the liner?
