For the world's super-rich, luxury cars and private jets are some of the ultimate status symbols attainable. During the summer months, however, nothing screams affluence quite like a vacation on a superyacht and docking in some of the world's most exclusive marinas. Without doubt, the Mediterranean is the top destination worldwide for billionaire yacht owners. Every summer, sun-soaked harbors in Croatia, Italy, France, Spain and other Mediterranean countries are jam-packed with yachts to the point that finding a place to dock can prove a nightmare. This is even true in the most expensive marinas where net worth matters little during the summer season when competition for berths is highest.