RMS Queen Mary 2 (also referred to as the QM2) is a British transatlantic ocean liner. She has served as the flagship of Cunard Line since succeeding Queen Elizabeth 2 in 2004. As of 2022, Queen Mary 2 is the only ocean liner (as opposed to a cruise ship) still in service. The ship was officially named Queen Mary 2 by Queen Elizabeth II in 2004 after the first of 1936. Queen Mary had in turn been named after Mary of Teck, consort of King George V. With the retirement of Queen Elizabeth 2 in 2008, Queen Mary 2 is the only transatlantic ocean liner in regular service between Southampton, England, and New York City, United States. The ship is also used for cruising, including an annual world cruise. She was designed by a team of British naval architects led by Stephen Payne, and was constructed in France by Chantiers de l'Atlantique. At the time of her construction, Queen Mary 2 was the longest, at , and largest, with a gross tonnage of , passenger ship ever built. She no longer holds these records after the construction of Royal Caribbean International's (a cruise ship) in April 2006, but remains the largest ocean liner ever built. Queen Mary 2 was intended for regular scheduled crossings of the Atlantic Ocean; the final construction cost was approximately $300,000 per berth. The cost was increased by the high quality of materials; having been designed as an ocean liner, 40% more steel was required than for a standard cruise ship. Queen Mary 2 has a maximum speed of just over and a cruising speed of , which is faster than a contemporary cruise ship. Instead of the common diesel-electric configuration, Queen Mary 2 uses integrated electric propulsion to achieve her top speed. Diesel engines, augmented by gas turbines, are used to generate electricity for electric motors for propulsion and for on-board use. Queen Mary 2s facilities include fifteen restaurants and bars, five swimming pools, a casino, a ballroom, a theatre, and the first planetarium at sea. Characteristics Queen Mary 2 is the flagship of Cunard Line. She was constructed to replace the ageing Queen Elizabeth 2, which was the Cunard flagship from 1969 to 2004 and the last major ocean liner built before Queen Mary 2. Queen Mary 2 had the Royal Mail Ship (RMS) prefix conferred on her by the Royal Mail when she