In this September 1, 2015 photo, street artists Jenaro de Rosenzweig, left, and Alejandro Revilla pose for a portrait behind a restaurant's window covered with a mural by artist Francisco Munoz, signed with his artist's name below, in the Roma Norte neighborhood of Mexico City. Rosenzweig and Revilla founded the “Street Art Chilango” cooperative in March 2013, which is filling neighborhoods with public art by local street artists. (Photo by Rebecca Blackwell/AP Photo)

Anna Sloan and Vicki Adams of Britain sweep during a match against Olympic Athletes from Russia in Session 1 of the Women' s Round Robin curling competition at the 2018 Winter Olympic Games at Gangneung Curling Centre in Gangneung, South Korea on February 14, 2018. The British team won the match convincingly, 10-3. (Photo by Cathal McNaughton/Reuters)

Members of the London School of Samba at the start of the Grand Finale of Notting Hill Carnival in London on August 29, 2022 which has returned to the capital for the first time in three years after being cancelled due to the Covid-19 pandemic. Europe's largest street festival celebrates Caribbean culture and is expected to welcome over 1 million people each day. (Photo by Stephen Chung/Alamy Live News)

Members of the Beltane Fire Society take part in Samhuinn Fire Festival on October 31, 2023 in Edinburgh, Scotland. Once celebrated from October 31 to November 1 by ancient Celts, Samhain, pronounced “SOW-in” or “SAH-win”, marked the shift from the brighter to the darker half of the year and was seen as a time when the boundary between the physical and spirit worlds was thought to weaken, influencing the development of contemporary Halloween customs. (Photo by Murdo MacLeod/The Guardian)

Drag Race UK alumni, Cheddar Gorgeous in the window of a Primark store in Manchester to celebrate the opening of the Photo by Fujifilm x Primark concession in Manchester on Wednesday, November 1, 2023. Fans are invited to visit the instore concession on the first floor in Primark on Market Street where Cheddar Gorgeous will be in a garment made up of over 1,000 Fujifilm INSTAX prints and designed by local fashion creator and artist, Mariusz Malon. (Photo by James Speakman/PA Wire)

Badminton School sixth form pupils (L-R) Lucy Warden, who got 3 A* and is off to study English at Durham, Sam Crumpton, who got 1 A* and 2 A's and is off to study to be a vet at Cambridge and Madeline Sunter, who got 2 A* and 1 B, and is off to study fashion at St. Martins, celebrate their A-level results on August 18, 2011 in Bristol, England. With another record year for A-level results, sixth-form students face a scramble for university places in the final year before tuition fees rise. According to the examination bodies the pass rate rose for the 29th successive year to hit 97.8 percent, while around one in 12 exams achieved the top A* grade. (Photo by Matt Cardy/Getty Images)

The World Bodypainting Festival held from July 4 to 6 at Lake Worthersee in Austria's southern Carinthia province included artists from around the world, drawing visitors to the “Mecca of Bodypainting”, according to the World Bodypainting Association. Photo: World Bodypainting Festival 2014. Photographed July 4th in Poertschach am Woerthersee, Austria July 4, 2014. (Photo by Jan Hetfleisch/Getty Images)

Son doong cave is a cave in Phong Nha-Kẻ Bàng National Park, Bố Trạch district, Quảng Bình Province, Vietnam. Currently the biggest known cave in the world, the cave is located near the Laos-Vietnam border. Inside is a large, fast-flowing underground river.
In early August 2013, the first tourist group explored the cave on a guided tour at a cost of US$3,000 each. The group had six members from Australia, Norway, Russia and USA and spent 7 days and 6 nights for the tour. Next exploration trips will be arranged.