Ijen volcano in East Java contains the world's largest acidic volcanic crater lake, called Kawah Ijen, famous for its turquoise color. The active crater measuring 950x600 m is known for its rich sulfur deposits which are being quarried. The volcano is one of several active strato volcanoes constructed over the 20 km wide Ijen caldera, the largest caldera in Java. Eruptions from Ijen are very hazardous because of the risk of the lake draining to form catastrophic lahars. You will take a ferry from Gilimanuk harbor in west Bali to Ketapang harbor in East Java. The trip will started from the regency of Banyuwangi and there will be a organized Jeep 4x4 will take you to the starting point passing the steep road and forest to trek to the Ijen crater. On the way trekking to the crater, you will often meet a lot of workers carrying down the sulfur of no less than 80 – 90 kg on his shoulder. Reaching on the rim of the crater, you will continue the trip down to the lake and to the center of steam where you’ll see the blue fire and a hundred of workers to digging the sulfur. This is one of the most dangerous job of the world.