Mount Ijen is an active stratovolcano located in Banyuwangi City, East Java, Indonesia. It’s famous for its striking sulfuric lake and the mesmerizing phenomenon of blue fire, which is caused by the combustion of sulfuric gases. The volcano stands at about 2,386 meters (9,183 feet) tall and is part of the Ijen volcanic complex, which is made up of several craters and volcanic peaks.

One of the main attractions of Mount Ijen is its crater lake, which is the largest acidic lake in the world, with a pH of around 0.5 (extremely acidic). The blue fire phenomenon is a result of sulfur gas igniting as it comes into contact with the oxygen in the air, and it can be seen at night in the crater.

The area around the volcano is also known for sulfur mining, where local workers carry heavy loads of sulfur out of the crater. The conditions are harsh, and the workers face significant health risks due to the toxic gases.

The Ijen Crater and its surroundings are part of a larger protected area called the “Ijen Reserve,” a popular spot for hikers and tourists seeking to witness its natural beauty.