Sulphur Caldron

Sulphur Caldron lies on the edge of one of the most active areas of Yellowstone's buried volcano, where sulfur-rich gases rise furiously and fill the pool with sulfuric acid, making it ten times more acidic than lemon juice and almost as acidic as battery acid. Billions of thermoacidophiles thrive in this muddy pool by converting hydrogen sulfide gas into sulfuric acid, and that acid breaks soil and rock into mud. These microorganisms are adapted to extremely hot, acidic conditions that would be deadly to humans.

Wyoming · United States