The Blue Lagoon (Bláa Lónið in Icelandic) is a set of geothermal pools fed with water from the Svartsengi Geothermal Power Plant. Minerals and algae give the water its distinctly blue color. Next to the natural pools, the Blue Lagoon also features a wellness spa where you can go for a swim in the hot water and a private clinic, specialized in treating skin diseases with the lagoon's mud and water.