Tens of thousands gathered in Saint-Nazaire, France  to see off the world’s biggest ever cruise ship: Royal Caribbean’s Harmony of the Seas, as it set sail for the first time on Sunday.

At 1,187 feet long, the $1.5 billion ship is longer than the Eiffel Tower  and holds the record for being the widest cruise ship ever built - boasting a 6,360-passenger and 2,100 crew capacity.

The ship has been likened to a floating city, with 16 decks, over  2,500 staterooms, 20 dining venues, 23 swimming pools, a skating rink, slides and a park with more than 10,000 plants and 50 trees.

Over 70,000 well-wishers gathered to see the ship out of the the French shipyard where it has been under construction fo the past 32 months. The ship was headed for Southampton in southern England and will embark on its official maiden voyage May 22 to its new home port of Barcelona.