This Chlorine-Free Pool Is Biofiltered and Freaking Beautiful

'Tis the season for stripping down and getting wet in the great outdoors. Unfortunately, the chlorine and chemicals used to keep man-made, al fresco watering holes clean can do a number on sensitive skin, which makes this Swiss pool all the more appealing; Herzog & de Meuron designed this beautiful lagoon with biofilters. Au naturel, ooh la la!