Volcanoes already make for some of the world’s most spectacular photography. Kawah Ijen, a volcano in East Java, Indonesia, and French photographer Olivier Grunewald take it to a whole other level: Kawah Ijen spews out eerie blue flames at night.
If you watched the awesome BBC documentary series Human Planet, you’ve seen Kawah Ijen before. The volcano is known for its huge sulfur deposits, thanks to a vent near its acidic crater lake.