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.

U.S. Marine Lt. Ben Reid from 1/2 Charlie Company of Task Force Tarawa waits to be medivaced after being hit with shrapnel and a machine gun round, in the southern Iraqi city of Nasiriyah, on March 23, 2003. The Marines suffered a number of deaths and casualties during gun battles throughout the city. (Photo by Joe Raedle via The Atlantic)

A Grey Seal pup and it's mother lay in the mud at the Lincolnshire Wildlife Trust's Donna Nook nature reserve on November 24, 2014 in Grimsby, England. Seal pup numbers have increased on last year with over 800 pups born at the reserve so far. Large bull seals are the first to arrive at the reserve in late October or early November where they will wait for females. (Photo by Dan Kitwood/Getty Images)

A long-tailed macaque grabs a necklace from a statue during the annual Monkey Buffet Festival at the Pra Prang Sam Yot temple in Lopburi, north of Bangkok November 30, 2014. The festival provides food and drinks to the local monkey population, which numbers more than 2,000, to thank them for drawing tourists to the town. (Photo by Damir Sagolj/Reuters)

A monkey catches knives as it balances on a board during a daily training session at a monkey farm in Baowan village, Xinye county of China's central Henan province, February 2, 2016. Baowan village of China's central Henan province appears to be your average farming community from the surface, but at a closer look, one can hear monkey hoots from every direction. Although no official number exists, villagers say that they have been a breeding ground for both monkeys and monkey trainers for centuries. (Photo by Jason Lee/Reuters)

A migrant woman pulls a girl out of the water as refugees and migrants arrive on an overcrowded dinghy in rough sea on the Greek island of Lesbos, after crossing a part of the Aegean Sea from the Turkish coast, October 2, 2015. A record number of at least 430,000 refugees and migrants have taken rickety boats across the Mediterranean to Europe this year, 309,000 via Greece, according to International Organization for Migration figures. (Photo by Dimitris Michalakis/Reuters)

Two men cross the street in front of a burned-out bus standing beneath a residential building, in the district Neukoelln in Berlin, Germany, Tuesday, January 3, 2023. People across Germany on Saturday resumed their tradition of setting off large numbers of fireworks in public places to see in the new year. The bus was set on fire during the New Year's celebrations. (Photo by Markus Schreiber/AP Photo)

A cat and a dog stray along a side street in Las Pinas city, Metro Manila, Philippines, 02 July 2023. A significant number of dogs and cats left wandering in streets could lead to potential health hazard due to rabies. Amidst Covid-19 pandemic, displaced pet owners who lost their job because their employers closed or lost business were forced to leave their animals in the city as they migrate elsewhere. (Photo by Francis R. Malasig/EPA)