A swimming pool would immediately make us think about that exciting wave pool at the water park or the one at our favorite hotel. However, there are some very impressive swimming pools out there in the world that cost millions of dollars to construct and maintain. They are built using state of the art technology and boast of having sophisticated features like fountains, water slides and what not. The intricate detailing that go behind the construction of these swimming pools is the main reason for their extravagant budget. And while some of these pools may be privately owned, there are some that are open to the public. So without further ado, we present to you some of the most expensive public as well as private swimming pools ever built.