Lake Hillier, is a lake on Middle Island, the largest of the islands and islets that make up the Recherche Archipelago, Western Australia.
The most notable feature of this lake is its pink colour. It is such a significant distinguishing feature of the archipelago that air passengers often take note of it. The colour is permanent, and does not alter when the water is taken in a container. The length of the lake is about six hundred metres (3/8 mile). The lake is surrounded by a rim of sand and a dense woodland of paperbark and eucalyptus trees with a narrow strip of sand dunes covered by vegetation separating it to the north from the Southern Ocean.
Links: en.wikipedia.org, www.atlasobscura.com