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 man rows a boat on the Dal Lake as a woman holds an umbrella during snowfall in Srinagar February 19, 2015. (Photo by Danish Ismail/Reuters)

A flock of starlings flies over Lake Leman on an autumn morning in the Lavaux near Grandvaux, Switzerland October 20, 2016. (Photo by Denis Balibouse/Reuters)

Security personnel patrol around West Lake in Hangzhou, Zhejiang Province, China, August 31, 2016. (Photo by Reuters/Stringer)

An Andean man and a woman, depicting Inca's legendary characters Manco Capac and Mama Ocllo, pose for a portrait in a Uros island at Lake Titicaca before a re-enactment in Puno November 5, 2014. The Uros islands are a group of 70 man-made totora reed islands floating on the lake, which according to Peru's tourism board iPeru is the world's highest navigable lake at over 4,000 meters above sea level. The Uros people fish and hunt, but tourism is their main source of livelihood. (Photo by Enrique Castro-Mendivil/Reuters)

Located at the foot of the Rocky Mountains on the North Saskatchewan River, the rare phenomenon occurs each winter in the man-made lake. Photo: Ice bubbles in Abraham Lake. (Photo by Chip Phillips/Rex Features)

In this photo taken Wednesday, October 29, 2014, a fisherman catches a fish near the shores of Lake Chivero, west of Harare. Illegal fishing can be hazardous in Zimbabwe, where poachers scan the banks for armed rangers and the water for crocodiles while they cast their rods. The country is in such a dire economic state that thousands of people, unable to find regular work, flock to Lake Chivero in hopes of catching fish, mostly bream, that they can sell for desperately needed income. (Photo by Tsvangirayi Mukwazhi/AP Photo)

Costumed participants of a lacquer and leather ship, the so-called “Torture Ship”, kiss before putting out to Lake Constance for a pleasure cruise at the harbor of Friedrichshafen, Germany, 29 June 2019. Hundreds of leather and rubber fans set sail for the boat trip through the night on Lake Constance. (Photo by Daniel Kopatsch/EPA/EFE)