Ireland's Lucy Mulhall (L) tackles USA's Ilona Maher during the World Rugby Women's Sevens series match between Ireland and the United States at the Allianz Stadium in Sydney on January 29, 2023. (Photo by Jeremy N.G./AFP Photo)

Japan fans pose for a photo outside the ground ahead of the Rugby World Cup 2023, Pool D match at the Stade De Nice, France on Sunday, September 17, 2023. (Photo by Mike Egerton/PA Images via Getty Images)

Canada's Mandy Marchak (R) is taken down by France's Pauline Biscarat during the final match of the Hong Kong Sevens rugby women's invitational cup in Hong Kong March 28, 2014. (Photo by Tyrone Siu/Reuters)

Julia Robinson of the Jillaroos scores a try during the rugby league Pacific Cup Women's Final match between the Australian Jillaroos and the New Zealand Ferns at CommBank Stadium in Sydney, New South Wales, Australia, 09 November 2025. (Photo by Mark Evans/EPA)

A three-month-old Sumatran tiger cub named “Bandar” shows his displeasure after being dunked in the tiger exhibit moat for a swim reliability test at the National Zoo in Washington, on November 6, 2013. All cubs born at the zoo must take a swim test before being allowed to roam in the exhibit. Bandar passed his test. (Photo by Manuel Balce Ceneta/Associated Press)

A pro-Russian supporter with the Russian national flag on her shoulders takes part in a meeting in Simferopol, March 6, 2014. Crimea's parliament voted to join Russia on Thursday and its Moscow-backed government set a referendum within 10 days on the decision in a dramatic escalation of the crisis over the Ukrainian Black Sea peninsula. (Photo by Vasily Fedosenko/Reuters)

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.

One-month-old cubs given birth by giant panda “Su Shan” are seen at Shenshuping giant panda base on August 17, 2021 in Aba Tibetan and Qiang Autonomous Prefecture, Sichuan Province of China. (Photo by He Haiyang/VCG via Getty Images)