This amazing image is of 'The Blue Lake' in Mount Gambier, South Australia.
This image has not been enhanced or had the colours changed. The blueness is seasonal and apparently can be even bluer than this... if you can imagine that!
There is a scientific reason for the blue colour "it revolves around the warming of the surface layers of the lake during the summer months to around 20 degrees Celsius (70 °F), causing calcium carbonate to precipitate out of solution and enabling micro-crystallites of calcium carbonate to form. This results in scatter of the blue wavelengths of sunlight. (thanks wikipedia)"
Anyway, enough of that, we love the lake just because it's blue! :)