In Search of the Blue Flame: Hiking to Ijen Crater, Indonesia

Have you tried hiking to a volcano crater at midnight, an uphill climb of 3-4 kilometers and at 11 degrees Celsius?

I have, in Kawah Ijen (Ijen Crater) here in East Java.

I can definitely say it’s been the highlight of my Indonesia trip so far, despite the early call time, the steepness of the slope, the sting of sulfur fumes, and the slightly dangerous trek going down to the bottom of the crater.

I’ve hiked up mountains countless times before, and some with similar challenges, but there’s a couple of things that set the Ijen volcano complex apart: its blue flame and the sulfur miners.

The rim of Ijen Crater.

Miners have been harvesting sulfur blocks in Kawah Ijen (2148 meters above sea level) for a long time — much in demand in the oil-refining business and the production of medicinal soaps and fertilizers — but it wasn’t until 2014, when a French photographer, Olivier Grunewald, released photos of Kawah Ijen that tourists began flocking to the area at midnight to see the blue flame.

The blue flame of Ijen Crater. ©Vins Carlos

Unlike what other websites are saying, it’s not the lava itself that’s colored blue, though. Kawah Ijen’s lava is the same as any other volcano.

The blue flame is produced when sulfur gas erupts from the rock face and encounters oxygen. It immediately burns with blue flame, and when it cools, it hardens to yellow sulfuric rock that miners break up and carry up the mountainside.

Sulfur rocks yet to be mined. ©Albert Cortes

A miner breaks up huge chunks of sulfuric rocks…

…while another breaks it up into smaller pieces.

Our group of Indonesian and international media influencers arrived at the campsite of Kawah Ijen at 2am. I was surprised at the number of people there; there must have been hundreds!

After our guide told us what to expect, I teamed up with friends to start the hike. I’m middle-of-the-packer, so I was soon left behind by the fast hikers, and left my slower friends behind as well.

Ready for the sulfur.

It took me an hour and 45 minutes to get reunited with my faster friends at the rim of the crater, and we found a few men there renting gas masks.

We had been given dust masks — the thin, white ones similar to the ones used in hospitals — but if you want to go down to the crater, it’s highly recommended to get the gas masks. Rent is IDR50,000 (around US$4) and it’s totally worth it!

Trail is steep, narrow, and rocky.

After asking several people around (by this time, we had already lost our guide; we assumed he was with the slower hikers), we then decided to go down to the bottom of the crater to see the blue flame up close.

The trail is rocky, narrow, and can be dangerous if you don’t have a light source. There were also hundreds of people going up and down, so rushing was out of the question.

Miner carrying sulfur rocks up the mountain.

Every now and then, we also met sulfur miners going up, each carrying two big baskets of sulfur, and cleared the way for them. If we were already having a hard time with just the clothes on our backs, how much more difficult was it for them with 75 to 90 kilos of rocks on their back?

My one regret was I didn’t bring extra money. I only brought enough to pay for the gas mask. I would have bought a few of the sulfur figurines that the miners were selling at IDR10,000 (US 75 cents) to at least help them out.

Buy some of these please.

When we got to the bottom of the crater, just before the lake, we were almost overcome by the sulfur smoke that the wind tossed our way every now and then. My eyes teared up, and even with the gas mask, I had difficulty breathing.

Maybe it was because I was a bit sick (with colds and cough), but I couldn’t imagine how the miners could keep on working there without using goggles and gas mask. I asked one why he didn’t use a mask, and he just pointed to the cigarette he was smoking. Does smoking help with the sulfur fumes? Or was he saying that he was used to it?

Toxic gas ahead!

Aside from the steepness of the slope going up to the rim from the crater, and the constant inhalation of the toxic fumes, there is one other risk that miners face every day just to earn around US$13 — occasional gas releases or phreatic eruptions (steam-driven explosions) that can kill, and have actually killed, miners.

With all these depressing facts, is it worth it to go hiking to Ijen Crater?

Definitely.

Tired but happy at the rim.

Looking down from the rim and into the crater gives one the feeling of being in another world. The beauty is stark, but it is there.

Seeing the miners lug those rocks up the mountain can also make you realize how strong the human spirit can be. No matter how hard the work, no matter how dangerous, people can do it to survive.

Miners carry up to 90 kg of sulfur. ©Albert Cortes

I didn’t get to see the turquoise waters of the Ijen lake — said to be the biggest highly acidic lake in the world — because we left soon after sunrise and the sulfur gases covered most of the area. You can probably see it if you stay until midday.

That said, here are a few tips to make your trip hiking to Ijen Crater a safe one.

Go there at sunrise to see this. ©Albert Cortes

Tips for Hiking to Ijen Crater

1. Don’t go down the crater if you have respiratory problems. The gas fumes can be really strong, and if you have asthma or have difficulty breathing sometimes, it can be dangerous for your health to go down there.
2. Get a guide. Sure, you can do this trek yourself by just following other people, but with a local guide, you can get a sense of history of the place, and have someone to help you figure out where to go and what to do.
3. Rent the gas mask. Trust me, you’ll need it.
4. Bring a head lamp or rent one. There is no light source anywhere in the area, so you definitely need a flashlight, or better yet, a head lamp.
5. Wear appropriate attire. It can get quite cold there, so having a winter jacket would help. It’s also a must to wear proper hiking shoes. No sandals please!
6. Have a hiking buddy. Make sure to team up with someone especially if going down the crater. You would want someone you know by your side if you trip and fall down the cliff! (Make sure though that it doesn’t happen to you!)
7. Bring money in small denominations. Those miners only earn $13 or so per day, by carrying heavy sulfur rocks up and down the mountain. Some of them sell sulfur figurines. For the love of God, buy at least one! If you also ask a miner to pose with you for a photo, give a tip.
8. Drink hot chocolate, coffee, or tea at the canteen almost halfway to the rim. When going down, stop at the canteen and order some tea (only IDR5,000 or less than 40 cents) or a bit of snacks. You’ll be helping the local storekeeper.

If you want to know more about Kawah Ijen and the sulfur miners, watch this BBC documentary.

You can also read here the health effects of repeated and long-term exposure to sulfur dioxide: Public Health Statement for Sulfur Dioxide.

Have you gone hiking to Ijen Crater (Kawah Ijen)? Would you want to?

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Aleah Taboclaon

Aleah Taboclaon is a location independent writer, editor, and the travel blogger behind Solitary Wanderer. She's partial to slow travel, and prefers extreme adventures like hiking and caving over sightseeing. She likes running (completed one marathon, training for the next!), diving (PADI open water diver), and traveling with her Kindle. Follow her on Instagram and Pinterest!

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