These mega-yachts are becoming veritable floating palaces with a large number of cabins. Most yachts over 50 meters have full-size gyms and a platform for landing a helicopter, and sometimes a hangar to shelter it. Some yachts even have a basketball court, infinity pools, a hospital, a recording studio, a cinema, a nightclub, conference rooms, a spa with a jacuzzi, sauna, hammam, massage and hairdressing rooms, or even a submarine. The price of a luxury yacht is difficult to assess if you don’t know all the details of the boat: interior fittings, engines, shipyard, etc., but the largest can exceed $100 million. The annual operating cost of a luxury yacht (maintenance, crew, insurance, fuel, ports, etc.) varies between 7 and 10% of the purchase price.

In fact, the longest yacht on the planet (as of 2014) is the Azzam, which measures 180 meters and belongs to Sheikh Khalifa bin Zayed Al Nahyan. In 2007, the largest custom yacht built, measuring 155 meters, belongs to the Sultan of Oman, Qaboos ibn Said. The average size of the world’s 100 largest yachts is 76.70 meters. End to end, they have a total length of approximately 8 kilometers.