The swimming pool at the Marina Sands Skypark, Singapore rises a giddy 200 metres above that futuristic city. The pool stretches across the span of the three towers forming the hotel and seems to spill, waterfall-like, all the way down to the streets below. The SkyPark takes infinity pools to a new extreme, while also encouraging swimmers who get too close to the edge to contemplate the infinite all on their own.
I'm surprised the largest swimming pool in the world in Chile wasn't on there! Here it is:
Gstadt palace must be a contender.
Peter Sellars made a great film there