34 of the World's Clearest Swimming Waters that include Honduras, Phillipines and Panama. Those are just 3 of 34. Spot number 6 is truly amazing! http://matadornetwork.com/trips/34-places-to-swim-in-the-worlds-clearest-water-pics/
The World’s Most Amazing Swimming Holes Technically, a “swimming hole” is any deep place for swimming in a stream, lake or river. But for this post the editors decided on a more ridged set of criteria: First, we considered only swimming spots that were inside some sort of hole in the earth. Second, we decided to count only naturally occurring swimming holes. Finally, we only considered swimming holes that offered temperate waters.
Our world has so many things that when you just LOOK at them, you think- oh! Swimming pool lanes! Race track! Grocery store! - but how to create that in another world, where the reader doesn't know the common things, like "otherworldly places?"