Officially the world’s deepest indoor swimming pool, Nemo 33 is located in Brussels, Belgium. It extends a mind-boggling 113 feet deep, it’s dark at the bottom! The temperature is controlled so swimmers can swim comfortably. There are also several underwater caves, allowing divers to explore aside from the main pool.
Diver Guillaume Néry is seen on Nemo 33 in this mesmerizing video. This will blow your mind.