POPULAR CRUISE LINES AND CRUISE SHIPS – who owns or operates them (Scroll down for a Full List of Popular Cruise Lines) Carnival Corporation owns and operates Carnival Cruises, Costa Crociere, Seabourn, Holland America, Princess Cruises, P&O, Cunard, Aida, and Iberocruceros. CARNIVAL CORPORATION (The World’s Largest Cruiseship operator, owns/operates more than 54% of all passenger […]