These photographs appear to show a spectacular underwater world making it ideal for scuba divers – in central Europe. Twelve metres of water covers trees, footpaths, benches and bridges that are usually accessible throughout the year. Visitors to the Green Lake in Tragoess, Austria, that is normally only one metre deep, can leisurely stroll around the picturesque lagoon. Photo: A diver crossing a bridge in the flood water. (Photo by Solnet/The Grosby Group)

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.

Myanmar civil security personnel escort an eight-metre tall wicker puppet from the French cultural group L'Homme Debout during a parade in Yangon city's Dala township on December 2, 2016 to mark the opening of the Mingalabar Festival. (Photo by Romeo Gacad/AFP Photo)

Iraqi army soldiers attempt to move their truck stuck in the mud near the village of Al-Boutha al-Sharqiyah, west of Mosul, on December 2, 2016, during a broad offencive by Iraq forces to retake the main hub city from Islamic State group jihadists. (Photo by Ahmad Al-Rubaye/AFP Photo)

Members of Japanese idol group Kamen Joshi (Masked Girls) in attires featuring images or names of U.S. President-elect Donald Trump, pose for a photo after their concert at their theatre in Tokyo's Akihabara district, Japan, December 12, 2016. (Photo by Toru Hanai/Reuters)

A group of people wearing Santa Claus hats and swimming suits participate in the 13th charity Great Santa Claus Run in downtown Budapest, Hungary, Sunday, December 11, 2016. (Photo by Balazs Mohai/MTI via AP Photo)

A Maasai boy bites a bull's heart during an initiation into an age group ceremony near the town of Bisil, Kajiado county, Kenya, August 23, 2018. Thousands of Kenyan boys had a blessing of milk and beer sprayed on them as part of a rare Maasai ethnic community initiation ceremony to mark their passing into early manhood. (Photo by Baz Ratner/Reuters)

A model Cindy Bruna presents a creation on a giant catwalk installed on a barge on the Seine River during a public event organized by French cosmetics group L'Oreal as part of Paris Fashion Week, France, September 30, 2018. (Photo by Stephane Mahe/Reuters)