Reaching the rim of the crater is not easy. Visitors have to hike for two hours to get to the rim and then make a 45-minute descent into the crater itself. At the base is a river of blue fire, created by the molten sulphur that escapes from cracks in the earth’s surface.
Ignited sulphuric gas here burns up to 1,000 degrees Fahrenheit and creates flares that can reach up to 16 feet in the air. The Ijen caldera is the largest, and arguably the most impressive, blue flame area on Earth. A highly acidic turquoise lake spans a kilometre across the base of the crater.
Though tourists visit the crater for an exciting day out, many locals spend their lives coming to Ijen to mine sulphur. They break apart cooled sulfur, which turns bright yellow when hardened, and carry it up the side of the caldera in baskets strapped to their backs.
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The baskets weigh up to 200 pounds and the miners climb almost 1000 ft to the crater rim. It’s another two mile trek down the mountain before they can have their baskets weighed. The daily exposure to volcanic gasses, against which the miners have little protection, adds to the difficulty and danger of this work, which pays from $8 to $15 per day.
Images via Reuben Wu