The actual crater at Kawah Ijen. The cloud to the right marks the location of the sulfur mine.
Kawah Ijen (Ijen Crater) is another one of East Java’s most popular natural tourism sites. Ijen is a complex of volcanoes located on the border between two regencies, or provinces, Banyuwangi and Bondowoso. The Ijen caldera is 20 kilometers wide, with the highest point being the Gunung Merapi (“Mountain of Fire”) stratovolcano. The actual Ijen volcano itself is located just west of Gunung Merapi and is known for the sulfurous gas emitted from its center and the “blue fire” phenomenon that can be witnessed in the crater at night. This blue fire is the result of ignited sulfuric gas, which shoots from cracks in the crater at temperatures of 600 deg Celsius (1,112 deg Fahrenheit). Since this phenomenon was mentioned a few years ago by National Geographic, night treks and ecotourism have become extremely popular. Some could argue that this trek would be banned in Western countries as a health and safety hazard to the general population, but that just adds to the general appeal.
The sulfurous gas cloud at Kawah Ijen. The darker, yellowish sections are the places where poisonous sulfuric gas exists.
We visited Gunung Ijen the day after our visit to Gunung Bromo, traveling straight across East Java and resting at a nearby resort in Bondowoso. We arrived at the Ijen base camp somewhere around 1:30 am and began our hike from there. If you choose to make the trip solo, you can rent or buy gas masks and warm clothing (think hats, scarves, gloves) from local hawkers in the area. You will definitely need a gas mask, so make sure you have one before you start your trek. Otherwise, the trip can be very dangerous. We had a guide (although I would argue that this wasn’t necessary) because I had booked everything – transportation, lodging, food, etc. – all at once just for simplicity’s sake and bundled it with my earlier visit to Mt. Bromo. Our guide rented gas masks for us from a friend for Rp. 20,000 each.
The Crater and the Trek
The 3-km-long trail up to Ijen Crater isn’t really your conventional hiking trail. Rather, in some spots, it’s the width of an actual dirt road, and the constant foot traffic has packed it down flat. I almost felt like we were making a pilgrimage of sorts because of the number of tourists shuffling along in a never-ending caravan at 1:30 am. We walked slowly, but we still climbed more quickly than many of the tourists we encountered and ended up passing a large percentage of those who started the climb before we did.
Interestingly enough, there are miners all along the trail calling “taxi” and pushing/pulling makeshift “wheelchairs” or wagons to transport tourists up the mountain. This is how miners try to make extra money. They charge an average of Rp. 200,000 per trip, with one person pushing and one to two people pulling. Just watching the miners with these wheelchairs looks painful. However, I guess one could argue that those with physical disabilities or those too weak to make the climb could utilize this option to still experience the crater without having to walk. The miners also offer rides down from the crater as well, which might be a good idea if you have joint pain like me and want to save your knees on the descent.
One of the “taxis” used by miners to transport visitors to and from the crater.
The walk is steep, but the nighttime temperatures tend to be cool (they can get down toward freezing, so make sure you’re prepared) and make for good climbing conditions. Even so, we ended up breaking a sweat before reaching the top of the crater. You’ll need a light source of some sort, so I recommend either a headlamp or a flashlight. If you don’t have one, you can rent these too from the hawkers down at the base.
The Crater and the Sulfur Mine
The Ijen crater is the site of an active sulfur mine that is still in operation by local miners. These miners will travel to the crater floor on foot and hand-carry woven baskets, laden with 70 – 100 kilos (165 – 220 lbs) of raw sulfur, out of the mine and down the mountain. The descent to the nearby Paltuding Valley is an additional 3 kilometers. Miners will usually make two trips per day, earning about Rp. 50,000 – 100,000 per day. This work is dangerous, so many miners are trying to enter the tourism business and become local guides instead. The miners often have insufficient protection against the toxic fumes (many do not even wear gas masks, only dampened cloths or balaclavas) and suffer from respiratory problems.
Left: Some of the baskets used by miners to carry sulfur out of the crater. Center: Me wearing my gas mask, something that miners often lack. Right: One of the large chunks of sulfur which originated in Kawah Ijen.
We commonly think of sulfur as bright yellow in color. However, when it is still molten, the sulfur is actually red. The miners have installed a network of ceramic piping in the crater to channel and condense the volcanic gases and molten sulfur. The sulfur travels through this pipeline and pools on the floor of the crater, eventually turning to that bright yellow color. The miners break this cooled sulfur into large chunks for transport back to the valley. There are approximately 200 active miners at Kawah Ijen who extract 14 tons of cooled sulfur per day. This incredible amount is actually only about 25% of the total daily output.
A basket full of newly mined sulfur.
When we arrived at the Ijen Crater just before 3:00 am, the sulfur mine was already buzzing with activity. You could see the headlamps of the miners twinkling among the rocks in the crater. Occasionally, you could see the blue fire from the viewpoint, but unfortunately there wasn’t a lot of activity on the morning of our visit. There are signs prohibiting visitors from entering the crater itself due to the high degree of danger presented by the noxious fumes and poisonous gas. This, of course, does not stop tourists from entering the crater in droves. We didn’t feel the need to immerse ourselves in a toxic gas cloud, especially since there wasn’t much blue fire to be seen, so we chose to stay out of the crater. Our guide also told us that he could lose his job if he led us down into the crater himself, and instead we sat off to the side and watched both the arriving tourists and the departing miners. My favorite moment was when a sulfur miner kept saying “Ding dong, ding dong” to alert tourists of his presence so that he could get around them. Some miners used English (“excuse me”), some used Indonesian (“permisi”), but his use of onomatopoeia was definitely the most creative.
The Crater and the Lake
Gunung Ijen boasts a 1-km-wide acidic lake, the largest of its kind in the world. The acid in this lake has a pH lower than that of battery acid and has the caustic strength to dissolve metal. At the edges, the lake has been shown to have a pH of just 0.5; in the middle, the pH has been measured as low as 0.13 due to the high concentration of sulfuric acid. In order to measure the acidity of the lake, a rubber boat was required to prevent corrosion.
A semi-clear glimpse of the turquoise waters of the acidic lake at Kawah Ijen.
Around 4:15 am, we began the last portion of the ascent around Kawah Ijen to a point where both the sunrise and the acidic lake are best viewed. This last section wasn’t particularly steep and took us up through some lush undergrowth. There was recently a fire at the crater, so many of the trees were still bare, their branches blackened. This was a lot more striking to see during our descent in the morning rather than by the light of our headlamps in the dark.
When the sun rose around 5:30 am, we weren’t able to see much due to the extreme presence of fog and clouds. We the wind blew in certain directions, we gained some semi-clear glimpses of the lake and the mountains beyond. We were able to see the turquoise color of the lake water through the mist, which was quite fascinating. While there were several groups of tourists nearby as the sun rose, most of the visitors to Kawah Ijen chose to remain around the lip of the crater or descend into it.
Left: An image of me standing above the acidic lake at daybreak. Right: The hills surrounding Kawah Ijen in the early morning mist.
On our walk back, we could see the outline of the hundreds of tourists lining the entrance to Kawah Ijen. The sight was almost surreal, reminiscent of birds on a telephone wire. In the daylight, we could see the lush greenery of our surroundings. We could also see the poisonous parts of the smoke cloud rising from Kawah Ijen; the parts with a yellowish hue were the parts containing the toxic gas. It was only while we were leaving the crater itself that the toxic fumes became so strong that they burned our eyes, and even this lasted only for a moment. During the rest of our visit to the crater, we would only put on our masks when the smell of sulfur became strong and suggested that the toxic fumes were reaching unhealthy (but not necessarily dangerous, yet) levels.
The silhouettes of the dozens of tourists lining the mouth of Kawah Ijen.
Getting There and Away
Kawah Ijen is not easily reached by public transportation, if at all. You’d be wise to arrange transportation in advance or rent your own vehicle. There is some lodging available close by due to the popularity of the trek, but you can also stay in the nearby cities of Banyuwangi or Bondowoso for convenience, especially if you’re in the market for accommodations with facilities such as wi-fi, hot water, and air conditioning.
However you choose to plan your visit to Kawah Ijen, you’re sure to have a unique and memorable experience. Stay safe, and happy trails!