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)

Dutch artist Maxim Gazendam works on his sand sculpture during the third edition of the European Championship Sand Sculpting 2014 in Zandvoort aan Zee, The Netherlands, 08 August 2014. Eight sculptors from different European countries will each create an impressive sculpture on the main theme “Music and Dance”. (Photo by Remko De Waal/EPA)

A navy diver storms into the gallery during a military display at Singapore's 52nd National Day celebrations at Marina Bay in Singapore August 9, 2017. (Photo by Edgar Su/Reuters)

A diver in a pool at the Army 2021 International Military and Technical Forum, at the Patriot military park in Moscow Region, Russia on August 22, 2021. (Photo by Sergei Karpukhin/TASS/Alamy Live News)

A diver dressed as “Mermaid of the Serpent Depths” performs in front of a sign marking the Lunar New Year of the Snake inside an aquarium at Manila Ocean Park on January 28, 2025. (Photo by Jam Sta Rosa/AFP Photo)

A diver dressed in a Santa Claus costume swims with a penguin at Sunshine Aquarium during preparations for the upcoming Christmas special event in Tokyo on December 1, 2025. (Photo by Kazuhiro Nogi/AFP via Getty Images)

Those lights are actually bioluminescent shrimp, better known as sea fireflies, or, in Japan, as “umibotaru”. Visible every year from May until the end of October, they live in the sand around very shallow sea water and are often seen floating between the extremes of high and low tides. Here: Bioluminescent sea fireflies glittering like diamonds on the rocks and sand. Okayama, Japan. July 2016. (Photo by Trevor Williams/Jonathan Galione/Getty Images)

Workers unload baskets of sand from ships in Gabtoli Launch Ghat, Dhaka, Bangladesh in the first decade of February 2025. (Photo by Rakibul alam Khan/Solent News)