The Dieng Volcanic Complex is a volcanic complex located on the Dieng Plateau in Central Java, Indonesia, a complex of volcanoes. The volcanic complex consists of two or more stratovolcanoes, more than 20 small craters, and Pleistocene to Holocene-age volcanic cones. It covers a 6 by area. The Prahu stratovolcano was truncated by a large Pleistocene caldera and then filled by parasitic cones, lava domes, and craters which is 120 C. Some of them are turned into lakes. Toxic volcanic gas has caused fatalities and is a hazard at several craters. On 20 February 1979, 149 people died of gas poisoning in Pekisaran Village on the plateau near the Sinila Crater. The area is also home to a major geothermal project.