Royal Caribbean Cruises takes to the waves to see the sights. The world's second-largest cruise line (behind the combined Carnival Corporation and Carnival plc behemoth), the company operates about 40 ships with nearly 10,000 berths overall. Its three main brands -- Royal Caribbean, Celebrity Cruises, and Pullmantur Cruises -- carry about 4 million passengers a year to nearly 500 ports, including ones in North and South America, Asia, Australia, the Caribbean, and Europe. Its other brands include Azamara Club Cruises, CDF Croisières de France, and a 50% joint venture interest in TUI Cruises. In addition, Royal Caribbean operates land-based tours and expeditions through Royal Celebrity Tours.