Naturbad, biologically filtered bathing lake, in Riehen in Switzerland by Herzog and de Meuron
Natural swimming pool/pond.
Yan's pond 2013 | by Mark Housman
An alternative to chlorine pools, the BioTop Natural Pools use plants to keep water clean and clear: http://www.biotop-natural-pool.com/referenz-teiche.html
Small, Natural Pool
natural pools | Natural Swimming Pools & Ponds Sheffield, Yorkshire - Garden Style
Lagoon and swimming pool by Chris Heiler, via Flickr
The glorious natural swimming pool at Il Paluffo, near Florence and Sienna, Italy
Caresse de fin d'été ...
Lap pool idea for hubby! 10 Eco-Friendly Natural Swimming Pools