Francisca Gomez stands at an entrance to her home, a cave where she has been living for the past 50 years, in the mountains on the outskirts of Chusmuy, Honduras April 21, 2015. The 75-year old widow receives help from neighbors and friends and she makes a little money by selling wood she collects, according to a local newspaper. (Photo by Jorge Cabrera/Reuters)

A winter swimming enthusiast dives into a partly frozen lake in a partly frozen lake in Shenyang, in northeastern China's Liaoning province on January 25, 2022. (Photo by AFP Photo/China Stringer Network)

A pilgrim prays at Mount Al-Noor, where Muslims believe Prophet Mohammad received the first words of the Koran through Gabriel in the Hera cave, ahead of the annual haj pilgrimage in the holy city of Mecca, Saudi Arabia September 7, 2016. (Photo by Ahmed Jadallah/Reuters)

Vietnam’s Son Doong cave, the largest in the world, could hold a 40-story skyscraper inside. The pristine ecosystem has its own river and jungle. Despite its size, Son Doong wasn’t discovered until 1991. It was lost again for nearly two decades and was fully explored for the first time in 2009. (Photo by Jason Speth/HuffPost)

“The Net thrower”. The fisherman are conducting activities on Situgunung Lake. Photo location: Situgunung lake, Sukabumi, West Java, Indonesia. (Photo and caption by Dody Kusuma/National Geographic Photo Contest)

The Maijishan Grottoes are a series of 194 caves cut in the side of the hill of Majishan in Tianshui, Gansu Province, northwest China. This example of rock cut architecture contains over 7,200 Buddhist sculptures and over 1,000 square meters of murals. Construction began in the Later Qin era (384-417 CE).

A woman rides a mechanical bull before participating in the 4th annual Running of The Bulls October 15, 2011 in Cave Creek, Arizona. (Photo by Joshua Lott/Getty Images)