A woman, with her face covered with colored powders, dances during the Holi Festival of Colors in Lisbon, Sunday, September 15 2013. The festival, which is mainly celebrated during the Hindu spring festival Holi in some regions of India and Nepal, has become popular among people in other communities. (Photo by Francisco Seco/AP Photo)

Hemispheric color differences on Saturn's moon Rhea are apparent in this false-color view from NASA's Cassini spacecraft in this March 2, 2010 file photo. (Photo by Reuters/NASA/JPL/SSI)

Smeared in colored powder fashionable women wearing sun glasses celebrate Holi, the Hindu festival of colors, in the Encino section of Los Angles on Sunday, March 24, 2024. (Photo by Richard Vogel/AP Photo)

A design studio has launched its own dogs of war – by cleverly blending iconic Second World War planes with their canine counterparts. Photo: Wellington bomber with Golden Retreiver camoflage. A design studio has launched its own dogs of war – by cleverly blending iconic Second World War planes with their canine counterparts. (Photo by BNPS)

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.

Vietnam's Khuat Phuong Anh (R) celebrates winning the women's 800m final during the 31st Southeast Asian Games (SEA Games) at My Dinh National Stadium in Hanoi on May 16, 2022. (Photo by Navesh Chitrakar/Reuters)

Runner-up; Hon Yen marine ecosystem. Phu Yen, Vietnam. Every year between May and August, the coral of this rich and diverse ecosystem becomes exposed at low tide. (Photo by Truong Hoai Vu/Royal Society of Biology Photography Competition)

A boat commutes across the Mekong river in Phnom Penh on August 8, 2014. The Mekong is the world's twelth longest river running from the Tibetan Plateau through China's Yunnan province, Myanmar, Laos, Thailand, Cambodia and Vietnam. (Photo by Tang Chhin Sothy/AFP Photo)