Ocean liner RMS 'Queen Mary', 20th century. Docked in harbour. Built by John Brown & Co on Clydeside for the Cunard White Star Line, the 81,000 ton Queen Mary was the largest ocean liner in the world when she was launched in 1934. Apart from an interlude as a troopship during World War II, she dominated the transatlantic route, together with her sister, the 'Queen Elizabeth', until she was retired from service in 1967. Since then she has been a hotel and tourist attraction moored at Long Beach, California.