The Kawah Ijen volcano found in Indonesia's East Java province is one of the largest sulfur mines on the planet. At night, the Ijen mine offers an amazing spectacle of fire and lights that creates an alien landscape around the volcano.
Photographer Olivier Grunewald and his friend Régis Etienne have made several trips to this dangerous location after they heard about it back in 2008, to capture still images and video footage of this surreal landscape.
Recently, Olivier has spent 30 nights in the crater of the Kawa Ijen volcano, surrounded by extremely corrosive gas, in order to create a documentary film that shows the tough life of the people who work here, even at night, facing flames that sometimes reach up to 5 meters (16 feet) in height to double their modest income.
Check out the photo gallery below to get a quick glimpse of the amazing blue lava that flows from the volcano every night.