The Royal Caribbean-owned Icon of the Seas will begin its first official cruise later Saturday, sailing away from Miami and toward the Caribbean. The world’s largest cruise liner’s first official trip, which will go seven nights, comes about two months after builder Turku Meyer transferred ownership over to Royal Caribbean and just a couple weeks after the ship first reached its home port in southern Florida. The Icon of the Seas owes its title of world’s largest cruise liner to its nearly 1,200-foot length and its nearly 248,700 gross tons. It also has 20 decks, all but two of which...