Ijen Crater is also a traditional place of sulfur mining and fro in the former arena eruption crater that is still active. Mount Ijen itself is in the area of Ijen Crater Tourism and Travel Park Reserve in Licin District, Banyuwangi Regency and Klobang district, Bondowoso regency. Ijen Crater is where the largest sulfur mine in East Java are still using traditional means. Ijen has a sulfur source sublimat seemingly inexhaustible used for various industrial purposes chemistry and purification of sugar. Ijen Crater is one of the world’s most acid with caldera walls as high as 300-500 meters wide crater reached 5,466 hectares. The crater in the middle of the caldera is the largest on the island of Java with a size of 20 km. The size of the crater itself is around 960 meters x 600 meters. The crater is located at a depth of more than 300 meters below the caldera wall.
Water crater bluish-green calm but tourists are not allowed to descend because water crater volume of approximately 200 million cubic meters of heat reaches 200 degrees Celsius. The degree of acidity is very high crater close to zero so that it can dissolve the human body even clothes quickly. Under the crater glowing api biru (blue fire) of liquid sulfur flowing endlessly to be dried by the wind then became a rock and enumerated the miners. The most appropriate time to see the beauty of Ijen in the early morning between 02.00 to 04.00. At that time you can see how the flames of blue (Api Biru) from the bottom of the crater.
If tourists want to get down to the bottom of the crater to see the blue flame then it must be accompanied by a guide. Wear a mask and goggles it’s because in addition to a very pungent smell of sulfur, sulfur fumes from the activities of the miners will easily attack and create an eye sore. This crater is large bluish-green lake with fog and smoke of sulfur that is fascinating.
Sumber dari : http://www.indonesia.travel/id/destination/293/kawah-ijen