Royal Caribbean’s Symphony of the Seas, the World’s largest cruise ship will be officially launched this month but won’t sail the Caribbean until October.

The fourth Oasis-class ship from the cruise line, which is just slightly larger that its sister ships, will officially inherit the bragging rights in a handover ceremony on March 23.

The 228,081-ton, 1,188-foot-long ship has been under construction at STX France shipyard in St. Nazaire France since October 2015, but now the finishing touches are taking place. The ship completed four days of sea trials in the Atlantic off the coast of France in mid-February undergoing more than 80 tests for seaworthiness.

Royal Caribbean’s Symphony of the Seas is the fourth Oasis-class vessel, set to debut in spring 2018. It will be the world’s largest cruise ship and sail out of Miami beginning fall 2018. “All the ship’s systems were put into service at sea,” reads a statement from STX France. “The performances expected during these presentations were validated each time.”

The Oasis-class vessels have each held the title of World’s Largest Cruise Ship, certified each in turn by Guinness World Records. Each one has been slightly larger than the last, with Oasis of the Seas first inheriting the title almost a decade ago when it debuted in 2009, followed by Allure of the Seas in 2010 and Harmony of the Seas in 2016.

Each of the four ships can hold close to 7,000 passengers. Symphony of the Seas has a maximum capacity of 6,680 guests with 2,200 crew. At double capacity, though, the guest count is 5,518 from 2,759 staterooms.

The new ship features the same design, with seven distinct neighborhoods and several of the same features that debuted on Harmony of the Seas or are mainstays across the fleet. Those include the 10-deck twisting dry slide The Ultimate Abyss, Twi-FlowRider surf simulators, a zip line, twin 40-foot rock climbing walls, ice skating rink and the AquaTheater.

Unique to Symphony of the Seas will be the “world’s largest laser tag arena,” in the Studio B space where the ice skating is performed. It will be transformed into a glow-in-the-dark venue themed around the fate of the last planets of the galaxy.

Also new to the fleet will be the Ultimate Family Suite, a two-level suite that will feature a slide, a floor-to-ceiling Lego wall, air hockey, movie-theater-style TV room with popcorn machine as well as a 212-square-foot wraparound balcony with its own climbing wall feature, bumper pool table and whirlpool. It’s a two-bedroom suite that can accommodate up to eight guests. Symphony will feature 28 more staterooms than Harmony of the Seas with a Royal Suite class, neighborhood balconies overlooking Central Park, virtual balconies on inside staterooms, and the highest number of ocean-view cabins at sea.

A new Mexican food concept called El Loco Fresh and casual seafood option called Hooked will debut on the ship. While other of the many dining options will be the same as other ships in the fleet including fusion food venue Wonderland, Jamie Oliver’s Italian dining venue, Japanese cuisine at Izumi, the Chops Grill steakhouse and 150 Central Park, which serves seasonal American cuisine.

Entertainment offerings include Broadway show “Hairspray,” original production “Flight” that is a humorous look at the history for flight, skating show “1977” and in the AquaTheater, a show titled “HiRo.”

One other feature coming to the ship will be the introduction of app-based mobile check in, that will be available in both Europe and when it comes to North America.

The ship will sail to Barcelona at the end of the month and then debut with a full set of passengers on the already sold out April 7, 2018 inaugural sailing. It will spend its first season of cruising in the Mediterranean. It then repositions to PortMiami on a 12-night transatlantic voyage that departs Oct. 28 and begins Caribbean sailings on Nov. 9 with the first seven-night cruise on Nov. 17.