Girls take a selfie at the haze shrouded Batanghari River bridge in Jambi, Indonesia Sumatra island, September 14, 2015. Indonesian islands are blanketed in the so-called “haze”, caused by slash-and-burn clearances on the islands of Sumatra and Borneo, which makes thousands sick, delays flights and pushes air quality to unhealthy levels in neighboring Singapore and Malaysia. (Photo by Reuters/Beawiharta)

An actor performs as a zombie during the “Train to Apocalypse” event at a Light Rail Transit (LRT) train station in Jakarta, Indonesia, 09 September 2022. The Indonesian capital's LRT operator modified train cars and stations into zombie apocalypse settings to promote the use of public transportations. (Photo by Mast Irham/EPA/EFE/Rex Features/Shutterstock)

Balinese children take part in a traditional mud bath known as Mebuug-buugan, a day after Nyepi – the “Day of Silence”, aimed at neutralising bad traits in Kedonganan village on Indonesia's resort island of Bali on March 23, 2023. (Photo by Sonny Tumbelaka/AFP Photo)

Residents make decorations mosque-shaped lamps to enliven the holy month of Ramadan in Pekanbaru, Riau Province on April 28, 2022. Muslims throughout the world are marking the month of Ramadan, the holiest month in the Islamic calendar, during which devotees fast from dawn till dusk. (Photo by Afrianto Silalahi/ZUMA Press Wire/Rex Features/Shutterstock)

Dancers perform the traditional Kuda Lumping in Bogor, Indonesia early November 2022. They are said to enter a trance-like state as they perform, and often claim not to remember the dance once they awaken. (Photo by Sita Gramich/Solent News)

In this Wednesday, April 3, 2019, photo, children play in the water on a beach as a mosque collapsed during the Sept. 28, 2018, earthquake is seen in the background in Palu, Central Sulawesi, Indonesia. The earthquake spawned a large localized tsunami that wiped out coastal areas, while liquefaction caused by the shaking turned entire neighborhoods into rivers of sludge. The disaster killed thousands of people, making it the world’s deadliest seismic event in 2018. (Photo by Tatan Syuflana/AP Photo)

Located in East Java, Indonesia, Kawah Ijen is a volcano is home to the largest acidic crater lake in the world. What turns the waters of the lake in the 1 km caldera its beautiful turquoise color are the highly sulfuric gases emitted from the volcano underneath.