Tree trunks and rocks are set up to support a leaning wall of Li Yonghua's damaged cave house in an area where land is sinking next to a coal mine, in Helin village of Xiaoyi, China's Shanxi province, August 2, 2016. (Photo by Jason Lee/Reuters)

Visitors are seen with giraffes on a bus at Safari Park in Kanchanaburi Province, Thailand, January 19, 2020. Kanchanaburi in western Thailand an area known for its waterfalls and caves. (Photo by Rachen Sageamsak/Xinhua News Agency/Eyevine)

“After an afternoon of hiking and exploring the caves of Rhossili Bay, West Glamorgan, we caught the sun breaking through the clouds”. (Photo by Megan Warren-Davis/The Guardian)

Young women walk through the cave of Saint George during Ashenda festival, at Saint George Church, in Lalibela, Ethiopia, on August 22, 2022. (Photo by Amanuel Sileshi/AFP Photo)

A Vietnamese bride is seen pushing the groom on a scooter during a photo shoot for their wedding in An Bang Beach outside Hoi An in Vietnam December 11, 2016. (Photo by Reuters/Stringer)

People carry lychee for sale on a motorbike on a street in Luc Ngan, Bac Giang province, Vietnam, 22 June 2016. Lychee output in Bac Giang province is expected to reach 130,000 tonnes this year. China is still Vietnam's main lychee export market so far, buying around 60 percent of the annual crop, according to official reports. (Photo by Luong Thai Linh/EPA)

U.S. President Donald Trump boards Air Force One to depart for Vietnam from Beijing Airport in Beijing, China on November 10, 2017. (Photo by Jonathan Ernst/Reuters)

Vietnam's Pham Hong Anh in action during her single dance final during the Southeast Asian Games' DanceSport competition in Mabalacat, Philippines, December 1, 2019. (Photo by Athit Perawongmetha/Reuters)