Kawah Putih is a crater lake inside a volcanic crater located in West Java, Indonesia. It is one of the two craters that make up Mount Patuha, one of the many volcanoes in Java.
It is an acidic lake (pH level ranging from 0.5 to 1.3), and changes color depending on its sulfur concentration, temperature, and oxidation state. These colors range from bluish to whitish green, or brown. It generally maintains a temperature around 10 degrees Celsius (50 degrees Fahrenheit). Sand and rocks near the lake have turned to white due to the interaction with the acidic water.
Kawah Putih is a popular tourist attraction, and has been open to the public since 1987.
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