Costa Crociere SpA , based in Genoa, comprises the brands Costa Cruises and AIDA Cruises.It boasts the largest fleet among all European operators, with a total of 25 ships in service, plus other two new units to be delivered by 2016. It is part of the group Carnival Corporation & plc , the world's largest cruise operator. Costa Crociere SpA is part of the group Carnival Corporation & plc, the world's largest cruise and is a member of the prestigious World's Leading Cruise Lines, Association of the major cruise lines in the world.