Here is probably the deepest pool in the world. It’s called Nemo 33 and is located in Brusseles, Belgium. It has five leves, with a dept of 33 meters. It cost 3.2 million euros, has a capacity of 2.5 million liters of water, and is used for practice diving.
What makes it so unique, beside the fact it is so big and deep, is that its water has a constant temperature of 30 degrees, acheived through solar panels which are placed on the roof of the building.