Lake Retba or Lac Rose lies north of the Cap Vert peninsula of Senegal, north east of Dakar in northwest Africa.
It is so named for its pink waters, caused by Dunaliella salina algae in the water that produce a red pigment that uses sunlight to create more energy, turning the waters pink. The color is particularly visible during the dry season. The lake is also known for its high salt content, which, like that of the Dead Sea, allows people to float easily.
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