Spanning 16 decks, 227,000 GT Harmony features 2,747 cabins and 5,479 passenger capacity at double occupancy.
The US$1 billion vessel surpasses her sister ships Allure and Oasis of the Seas as the world's biggest. Oasis and Allure, which were delivered in 2009 and 2010, respectively, are each 225,000 GT and have 2,706 staterooms for a double-occupancy capacity of 5,412.
Harmony of the Seas will have a few features that her sisters don't, most notably the slide with a 100-foot drop Ultimate Abyss. Riders plunge from Deck 16 to Deck 6 on the Boardwalk.
There will also be thrilling waterslides, three of them collectively named the Perfect Storm. Altogether, 4.7 mill pounds of water will fill 23 pools, hot tubs, 2 FlowRider surf simulators, waterslides and Splashaway Bay water park.
The molecular gastronomy experience Wonderland, that made its debut on Quantum of the Seas in 2014, is a 2-story restaurant on Harmony.
The first cruise of the new ship, a 4-day sailing, departs Southampton UK on May 22. The ship will spend summer season in Europe, sailing 7-day cruises out of Barcelona. In November, Harmony will arrive in Port Everglades, from where she will operate 7-day Caribbean cruises.