A young fan exchanges friendship bracelets with American singer-songwriter Taylor Swift as she performs onstage during “Taylor Swift | The Eras Tour” at Allianz Parque on November 24, 2023 in Sao Paulo, Brazil. (Photo by TAS2023 via Getty Images)

United States's Jessie Diggins celebrates winning the cross-country ski, women's Tour de Ski overall standings, in Val di Fiemme, Italy, Sunday, January 7, 2024. (Photo by Alessandro Trovati/AP Photo)

In this Wednesday, August 20, 2014 photo released by Red Bull, Maikel Melero of Spain warms up prior to the fifth stage of the Red Bull X-Fighters World Tour in the South African savanna of Pretoria, South Africa. (Photo by Joerg Mitter/AP Photo/Red Bull)

A girl rides a broomstick in front of a green screen at the new Harry Potter Studio Tour at Warner Brothers Leavesden Studios on March 23, 2012 in London, England. The studio, which includes the actual sets and special effects departments where the films were created and shot, goes on public display on March 31, 2012. (Photo by Dan Kitwood/Getty Images)

Spectators in colourful attire cheer as the pack of riders (peloton) cycles by during the 14th stage of the 111th edition of the Tour de France cycling race, 151,9 km between Pau and Saint-Lary-Soulan Pla d'Adet, in the Pyrenees mountains in southwestern France, on July 13, 2024. (Photo by Anne-Christine Poujoulat/AFP Photo)

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.

An installation of Canadian artists Caitlind Brown and Wayne Garrett is displayed during the Lumina Light Festival in Cascais September 14, 2014. Lumina Light Festival shows artworks of artists from several countries, which are displayed during a tour around Cascais. (Photo by Rafael Marchante/Reuters)

Prince Charles, Prince of Wales (R) and Camilla, Duchess of Cornwall (L) visit Seppeltsfield Winery in Barossa Valley, Australia, 10 November 2015. The royal couple are on a 12-day tour visiting seven regions in New Zealand and three states and one territory in Australia. (Photo by Daniel Kalisz/EPA)