As summer approaches, you might like to take a dip (don’t forget the sunscreen). Appearing as if you are at the edge of a waterfall, an infinity pool offers a beautiful sight from within and without.

How do you like to spa? Surrounded by trees and water and birdsong? Overlooking a lake with a horizon of distant mountains? Only after you’ve sweated it out on a 10-mile hike? Or maybe you prefer to ...