Miami, Florida – The Royal Caribbean’s Icon of the Seas has embarked on its seven-day maiden voyage from Port Miami, carrying nearly the population of a small city onboard. This $2 billion ship boasts 20 decks, 2,350 crew, 2,805 staterooms, and ample space for 7,600 passengers, making it the largest cruise ship in the world.

The luxurious vessel features a 55ft artificial waterfall, 40 dining venues and bars, seven swimming pools including a 40,000-gallon ‘lake’, 50 musicians and comedians, as well as a 16-piece orchestra. Additionally, the ship is powered by ‘eco-friendly Liquefied Natural Gas’ (LNG), which the Royal Caribbean claims to be 24 percent more efficient in terms of carbon emissions than required by the International Maritime Organization.

While the fuel used is said to be better than traditional marine fuel, environmentalists are concerned about the potential methane emissions from the ship. Methane, a powerful greenhouse gas and the second-largest contributor to climate warming after carbon dioxide according to NASA, is a major point of concern. The International Council of Clean Transportation points out that methane slips from LNG-fueled ships, such as the Icon of the Seas, can contribute to climate change.

Despite these concerns, the Icon is set to sail Caribbean voyages throughout the year from Miami, with itineraries featuring stops at ‘award-winning private island’ Perfect Day at CocoCay in The Bahamas. The ship was officially ‘christened’ on Tuesday by World Cup winner Lionel Messi and his Inter Miami teammates.

Lionel Messi placed a soccer ball atop a stand to ‘start’ the traditional breaking of a champagne bottle against the bow of the ship, a ceremony believed to bring good luck to the vessel and its passengers. The 36-year-old Argentine later called it a ‘privilege’ and expressed his hope for the ship to bring blessings to all who sail on it.