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)

The rarely seen blue sharks photographed by Saeed Rashid in British waters. Elusive blue sharks have recently been spotted off the south coast of England, having moved to the UKs warmer waters to hunt. The carnivorous sharks have been lurking off the coast of the popular British holiday destination, Penzance, in Cornwall. (Photo by Saeed Rashid/Caters News)

A child looks at a polar bear swimming under a water in its enclosure on a hot summer day at Prague Zoo, Czech Republic, July 30, 2015. (Photo by David W. Cerny/Reuters)

People wearing costumes attend the annual water-splashing festival to mark the New Year of the Dai minority in Jinghong, Yunnan province, April 13, 2015. (Photo by Reuters/China Daily)

The old church of Geamana village is seen partially submerged by polluted water tainted with cyanide and other chemicals near Rosia Montana, central Romania, March 24, 2014. (Photo by Bogdan Cristel/Reuters)

Nothing says Halloween like a jack-o'-lantern, but these professional carvings will blow your neighborhood pumpkin out of the water. (Photo by Frank C. Grace/Courtesy Jack-O-Lantern Spectacular)

A baby hippo swims under the water in its enclosure at Prague Zoo, Czech Republic, February 24, 2016. The baby was born on January 28, and is yet to be named. (Photo by David W. Cerny/Reuters)