A video of the spectacular scenes captured at a volcano crater "from another planet" has captivated users on Instagram.
The video was shared by @2troubletravelers, the Instagram account of Domi, 29, and Thomas, 34, a couple from Slovakia who visited the Ijen crater in Java, Indonesia on April 9. The clip has had 1.6 million views since it was posted on April 12.
A message overlaid on the video reads: "POV [point of view]: My husband convinced me to go for a night hike to the volcano crater."
The footage shows the couple wearing gas masks while climbing up the volcano by night, with mesmerizing, blue-colored fire trails blazing along the pathway. They are later shown standing at the top of the volcano at daybreak, overlooking a spectacular turquoise lake.
The couple told Newsweek: "The view from the top was incredible and we have never seen anything like this before. We have never seen a lake with such a color. But we also had respect for the nature and how powerful it can be. Also seeing the natural blue fire in nature was an amazing experience."
Domi, 29, and Thomas, 34, a couple from Slovakia, overlooking the lake at the Ijen crater in Java, Indonesia. The couple hiked by night to the top of the volcano crater.Domi, 29, and Thomas, 34, a couple from Slovakia, overlooking the lake at the Ijen crater in Java, Indonesia. The couple hiked by night to the top of the volcano crater.@2troubletravelers on InstagramThe viral footage was shared just days before a Chinese tourist plunged to her death last month during a guided tour of the Ijen, when she fell off the edge of the active volcano while posing for a photo, dropping from a height of around 246 feet, according to Hongxing News.
Ijen forms part of the Ijen UNESCO Global Geopark, which is comprised of Mount Ijen, the active volcano with its turquoise crater lake called Kawah Ijen, the most acidic lake in the world. The park also includes Belambangan Biosphere Reserve, which was designated as a UNESCO site in 2016.
The Ijen crater is known for its blue fire phenomenon, which results from the reaction between sulfur and oxygen.
"While most volcanoes produce red or orange fire, the high sulfur concentrations and temperatures, exceeding 360°C in Ijen crater, create a unique environment for the formation of blue fire. This phenomenon is observable only during nighttime due to the overpowering intensity of sunlight obscuring the visibility of the blue flames," UNESCO explains.
A stock image of the blue fire phenomenon seen at the Ijen volcano in Java, Indonesia which results from the reaction between sulfur and oxygen. A stock image of the blue fire phenomenon seen at the Ijen volcano in Java, Indonesia which results from the reaction between sulfur and oxygen. iStock / Getty Images PlusThe park's crater lake is another remarkable natural wonder marked by various geological processes.
UNESCO notes: "It contains chemical solutions resulting from the interaction of magmatic volatiles, rock-fluid interactions, evaporation, dilution by meteoric water, and the recycling of water through subsurface hydrothermal systems.
"Acting as a condenser for volatile water from shallow magmatic heat sources, the lake assimilates acidic magmatic vapors, which leads to the formation of highly acidic water," UNESCO adds.
'Most powerful experience in Indonesia!'
Domi, who was a university teacher for digital marketing, and Thomas, a former data analyst, quit their jobs to work as full-time content creators. The couple, who are currently on their "honeymoon around the world," have been traveling for seven months, with their most recent stop being Indonesia.
The night hike in the viral clip started around midnight and it took around 90 minutes to get to the base camp. "The first part of the hike was to the crater to see the blue fire, which is only visible during the night. The blue color is special because of the sulfur," the couple told Newsweek.
It took about an hour and a half to two hours to get to the blue fire and then another hour to get to the top of the volcano for the sunrise.
A caption shared with the viral post reads: "The most powerful experience in Indonesia! We have never seen place like this! It looked like place from another planet!"
Users on Instagram were blown away by the latest footage.
Userwildchasers_ said, "Woww!!! What an experience" and packinglife2travel said, "Wow wow, we really want to do it."
"I had no idea that something like this existed. Wow! Such an unique experience," wrote annas_exciting_adventures.
"We did this last year for our engagement! Honestly, the most magical experience!," said sinfulrayofsunshine.
A view of the turquoise lake at the Ijen crater in Java, Indonesia, which is the most acidic lake in the world. A view of the turquoise lake at the Ijen crater in Java, Indonesia, which is the most acidic lake in the world. @2troubletravelers on InstagramDo you have a travel-related video or story to share? Let us know via life@newsweek.com and your story could be featured on Newsweek.