World's largest cruise ship is 'as long as the Empire State Building'

On Saturday, Royal Caribbean's "Symphony of the Seas" left the French shipyard where it was built. Its first voyage with passengers is scheduled for March 31.

The massive ship is 18 decks high and almost as long as the Empire State Building. The ship boasts dozens of lounges, bars and restaurants as well as a skating rink, surf simulator and a giant water slide.

It can hold up to 6,680 passengers.

The ship will spend its first few months sailing in the Mediterranean out of Barcelona before moving to Miami to operate cruises to the Caribbean.