The "Freedom"-class ships are lengthened versions of the second-generation "Voyager"-class ship, and contain a Royal Promenade mall running much of the length of the ship, an ice skating rink, basketball court, several pools, a mini-golf course, and a rock wall. New features on the "Freedom" class include the FlowRider surfing simulator, the H2O Zone kids water play area, a boxing ring, and hot tubs cantilevered over the side of the ship. At 154,407 gross tons, the "Freedom"-class ships were the largest ships in the world from 2006, until the debut of the Oasis class in 2009.