Just for fun: The clearest lake in the world

Blue Lake in New Zealand's South Island has amazingly clear water. To give you an idea of just how clear it is, here's a comparison. If you filled a lake with distilled water, you'd be able to see down about 80 meters. If you stare into the depths of Blue Lake, you can see for up to 76 meters. 

That means you can get pictures like these.



Photograph: Klaus Thymann /Project Pressure


Hat tip: Not Exactly Rocket Science.