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)

French mounted bullfighter Lea Vicens is gored by her first bull and falls off her horse during the 31st day of the San Isidro bullfighting festival at Las Ventas bullring in Madrid, Spain, 10 June 2017. (Photo by Victor Lerena/EPA)

The social media star Demi Rose, 23, wows her fans and showed off her famous curves as she poses in a thong bikini and high heels for “I Saw It First” in Ibiza, Spain on Monday, June 4, 2018. (Photo by KP Pictures)

A bull hits a reveller during the first running of the bulls of the San Fermin festival in Pamplona, Spain, July 7, 2018. Each day at 8am hundreds of people race with six bulls, charging along a winding, 848.6-metre (more than half a mile) course through narrow streets to the city's bull ring, where the animals are killed in a bullfight or corrida, during this festival dating back to medieval times and also featuring religious processions, folk dancing, concerts and round-the-clock drinking. (Photo by Vincent West/Reuters)

English model Katie Price pictured going topless while on holiday with boyfriend Kris Boyson at Ammatara Pura Pool Villas resort in Thailand on July 13, 2018. The happy couple looked relaxed in matching yellow Bikini and shorts as they frolicked with each other by the pool as they enjoyed their first holiday together at exclusive resort in Thailand. (Photo by Backgrid UK)

A young Sikh boy shouts religious slogans during a procession ahead of the birth anniversary of Guru Nanak in Jammu, India, Wednesday, November 21, 2018. The birth anniversary of Guru Nanak, founder of Sikhism and first Sikh guru, will be marked on Nov. 23. (Photo by Channi Anand/AP Photo)

Chunhun (R), the leader of Japan's North Korea fan club called sengun-joshi, or military-first girls, and other members practice a Moranbong Band dance in Tokyo, Japan on November 2, 2017. (Photo by Toru Hanai/Reuters)

Drunk fresher is helped by students as she falls to the ground on night out at during the alcohol-fuelled Freshers’ Week in Birmingham, United Kingdom on September 18, 2017. Freshers are inducted during Freshers' Week – the first week of the Academic year – one of the busiest and most fun weeks of the year. (Photo by Caters News Agency)