The Blue Lagoon

The Blue Lagoon is actually a pale blue of effluent from the Svartsengi power plant, fuelled by seawater which has been heated after seeping beneath the lava. Cyanobacteria thrive in the water that emerges from the pipes. However, as the water cools in the air, the algae dies leaving an organic soup with an average temperature of 37°C and 2.5% salt content. The chemical content of the silica mud combined with the dead algae is believed to be therapeutic.

Great clouds of vapour rise from the water, parting occasionally to reveal the immense stacks and buildings of the power plant and moss-covered lava formations in the background. The bottom is lined with chalky rocks and slimy white silica mud.