A round circle of smoke coming from the mouth of the Etna volcano is seen in the sky during an eruption on the southern Italian island of Sicily April 11, 2013. Mount Etna is Europe's tallest and most active volcano. (Photo by Antonio Parrinello/Reuters)

Kelimutu is a volcano, close to the small town of Moni about 50 km to the east of Ende, Indonesia in central Flores Island of Indonesia.

“Mount Hua, or Hua Shan, or Xiyue located near the city of Huayin in Shaanxi province, about 120 kilometres (75 mi) east of Xi'an. It is one of China's Five Great Mountains, and has a long history of religious significance. Originally classified as having three peaks, in modern times the mountain is classified as five main peaks, of which the highest is the South Peak at 2,154.9 metres (7,070 ft)”. – Wikipedia

Photo: Trip to Xi'an 西安. (Photo by Grant Robinson)

A farmer tends to his field as Mount Sinabung releases pyroclastic flows in Tiga Pancur, North Sumatra, Indonesia, Saturday, June 13, 2015. The volcano, which was put on it highest alert level last week, has sporadically erupted since 2010 after being dormant for 400 years. (AP Photo/Binsar Bakkara)

This happy couple started married life on top of the world, having exchanged their vows on mount Everest. Dressed in a full suit and wedding dress, James Sissom and Ashley Schmieder spent days scaling the mountain range in order to be photographed in front of such a breathtaking backdrop. Here: James Sissom and Ashley Schmieder exchange vows on Everest. (Photo by Charleton Churchill/Caters News Agency)

Sunrise over the fields of stemmy grassland in Burscough, Lancashire, UK on September 14, 2020 with wrapped bales of hay prepared for silage, haylage for animal winter feed. (Photo by MediaWorldImages/Alamy Live News)

A girl goes to school just before sunrise in Frankfurt, Germany, Wednesday, December 11, 2019. (Photo by Michael Probst/AP Photo)

Icelandic horses play on a stud farm in Wehrheim Frankfurt, Germany, as the sun rises on Thursday, May 21, 2020. (Photo by Michael Probst/AP Photo)