Kawah Ijen

Kawah Ijen is an active volcano in Indonesia. The miners scale 2,600 meters tall (8,660ft) Kawah Ijen volcano trek up to the crater, then down to the shore of a 200-meter-deep crater lake of sulfuric acid, where they retrieve heavy chunks of pure sulfur to carry back to a weighing station. They do all this without any protective masks or gear.