An Acehnese female police officer wear a hijab on duty in the street in Banda Aceh, Indonesia, 27 March 2015. Indonesia National Police officially issued a regulation allowing female police officer to wear the Islamic hijab (heads craft) as a part of their uniform. Indonesia is the biggest Muslim population in the world. (Photo by Hotli Simanjuntak/EPA)

Rescuers pull dead whales ashore in Probolinggo, East Java, Indonesia, Thursday, June 16, 2016 during a mass rescue operation of stranded whales. Most of more than 30 stranded whales were managed to be pulled into the deep sea, an official said. (AP Photo/Trisnadi)

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.

A protestor gestures during clashes with police during protests against planned fuel price hikes on March 27, 2012 in Jakarta, Indonesia. Thousands of Indonesians students in big cities all over the county gathered to protest the governments plans to increase the price of subsidized fuel by 30 percent. The Indonesian parliament is currently debating the fuel hikes which would go into effect March 25, 2012 if approved. (Photo by Ulet Ifansasti/Getty Images)

Participants struggle to reach the prizes during a greased-pole climbing competition held as a part of the independence day celebrations in Jakarta, Indonesia, Sunday, August 17, 2014. Indonesia is celebrating its 69th independence from the Dutch colonial rule. (Photo by Dita Alangkara/AP Photo)

Students on their way home from school play in a river which has risen due to recent seasonal rains, in a remote village in Panca, Aceh province on January 22, 2021. (Photo by Chaideer Mahyuddin/AFP Photo)

Puryanti, a 29-year-old woman, and her 15-year-old nephew Raffi, cover themselves from head to toe in silver paint to become “manusia silver” (silver people), as part of their act to make a living, in Depok, on the outskirts of Jakarta, Indonesia, February 6, 2021. (Photo by Adi Kurniawan/Reuters)

A worker throws a cloth during a drying process at Sukoharjo near Solo, Central Java province, Indonesia, April 23, 2019 in this photo taken by Antara Foto. (Photo by Mohammad Ayudha/Antara Foto via Reuters)