Crater lake is accumulation of rain and ground water that fills in a volcanic crater. If the volcano is active and the lake is covering active vents, the water can be deadly. It is usually saturated with fumaroles gases and has greenish color. If the volcano is extinct or dormant, the water is fresh and exceptionally clear as there is no sediment in it.
Dieng Crater, East Java
Dieng volcano complex had been known for its frequent release of carbon dioxide, which sometimes results in fatalities. Local people called some area of the volcano as the “death valleys”. The emission
Tengger Caldera, East Java
Tengger volcano is the most visited volcano in Indonesia. Located in East Java, the mountain provides unforgettable experience. There are five overlapping strato volcanoes in the area, each truncated by a caldera. The most famous in the area is Mount Bromo. The famous lakes in Tengger area are Ranu Kumbolo, Ranu Pane and Regulo.
Kelud Crater, East Java
Mount Kelud is an unstable active volcano located in East Java that
Kawah Putih, West Java
Kawah Putih means “white crater”. It is located within Patuha volcano, an active volcano in West Java. The water is highly acidic as a result of high magmatic activity. Sulfur sediments on the bottom on the lake were mined during the first half of the 20th century. The lake is beautiful but is toxic.
Lake Ijen, East Java
This biggest crater lake in Java Island is located within Ijen Volcano in East Java province. It contains 36 million cubic meters of acid water and covered with sulfur cloud. The lake is very beautiful with a green turquoise color but very poisonous. Some said that Lake Ijen probably is one of the most toxic lakes in the world. Ijen crater is also a location of sulfur mining operation. The miners do the operation with traditional tools without any safety precaution. Tons of sulfur is carried down the mountain on foot. Each miner can carry 70-100kg sulfur on his basket per day. Ijen is best viewed in the morning between 8 – 9 am.