A thick veil of smoke erases the sky over Mount Ijen, the scent of burnt matches saturates the air.
The noxious material that seeps from the bowels of East Java’s active volcano is incongruous with human life—it stings the eyes, burns the lungs, and corrodes the skin. But since 1968, the sulfur miners of Mount Ijen have ventured into this unpredictable labyrinth of gas clouds and superheated fumaroles to extract “devil’s gold” and carry it back down the mountain— a portrait of bone-crushing physical labor.

Mount Ijen hosts one of the last remaining active sulfur mines in the world, and while its otherworldly vistas have captivated scientists and travelers for more than two centuries, in recent decades, the miners themselves have become a controversial tourist attraction. Every day, miners make the arduous trek up Ijen’s 9,000-foot slopes under the cover darkness before descending another 3,000 feet into the crater, where a network of man- made ceramic pipes funnels the gases responsible for precipitating elemental sulfur. Enveloped in toxic fumes and heat, they chip away at the hardened blocks and carry 150 to 200-pound loads back up the crater twice a day, earning an average of five dollars per trip.

Around 2 a.m. when the first miners begin their ascent, hundreds of tourists are already streaming across the flanks of Ijen to witness its iconic blue flames, which can only be seen at night. Its half-mile turquoise crater lake takes on an eerie glow in the darkness. Deceptively beautiful, it has a pH lower than that of battery acid—the largest acid lake on Earth, caustic enough to dissolve metal.

Considered a form of cultural heritage tourism, mine tours can be found around the world. Some researchers propose tourists are attracted to these sites because they elicit what philosophers have termed “the sublime”—a feeling of pleasure in seeing a dangerous but awe-inspiring object, like a violent act of nature.

Indonesia is situated on the Ring of Fire—a 25,000-mile seismically active belt of volcanoes and tectonic plate boundaries that frame the Pacific basin. It is estimated that 75 percent of all active volcanoes and 90 percent of earthquakes worldwide occur in this region.
About five million Indonesians live and work near active volcanoes, where farming soil is most fertile. Java alone is home to 141 million people—one of the most densely populated islands on Earth.

In March 2018, hundreds of people surrounding Mount Ijen were forced to evacuate their homes and 30 were hospitalized after the volcano spewed toxic gases.
Today, Indonesian and international scientists continuously monitor volcanic activity and are trying to find ways to mitigate future hazards.

(Text by Gulnaz Khan fo National Geographic)

Sulfur Road is the second chapter of “Beyond”: an investigation focused on the delicate relationship between man and the environment in its most extreme expressions. A project looking at humanity's hunger for the planet’s resources.

click to view the complete set of images in the archive