I saw a pool like this online a few years ago and always wanted to build one, and I was recently given the chance by a very good client of mine.
Needless to say, both the client and I are thrilled with the results, and the circular swimming area really gives the pool a more natural feel in my opinion.
Follow the link for more information, and to see the massive benefits of Natural Swimming Pools.
You can also see a wide variety of Natural Pools we have built, in our Photo Gallery.
Scroll through the gallery and click images to enlarge.