Visitors look over masses of ice formed around the Canadian “Horseshoe” Falls in Niagara Falls, Ontario, Canada, Thursday, February 19, 2015. (Photo by Aaron Lynett/AP Photo/The Canadian Press)

Members of the ice swimming club “Berliner Seehunde” (Berlin Seals) take a dip in the Orankesee lake as part of their traditional Christmas swimming session in Berlin, Germany, December 25, 2015. (Photo by Hannibal Hanschke/Reuters)

An arrow-head discovered in 2006 by Archaeologists of the University of Cambridge Archaeological Unit, is displayed by one of the team uncovering Bronze Age wooden houses, preserved in silt, from a quarry near Peterborough, Britain, January 12, 2016. Archaeologists said on Tuesday they had discovered what were believed to be the best-preserved Bronze Age dwellings ever found in Britain, providing an extraordinary insight into prehistoric life from 3,000 years ago. (Photo by Peter Nicholls/Reuters)

A girl gives a dog ice cream at dog beach and bar in Crikvenica, Croatia, July 12, 2016. The first Croatian beach bar specifically designed for dogs opens in the northern Adriatic town of Crikvenica, enabling canines and their owners to experience the joys of summertime together. Located at one of the few dog friendly beaches in the country, the bar's offer includes specially prepared ice cream, dog beer and snacks. (Photo by Antonio Bronic/Reuters)

Freya Smith aged three, leads one of Erth’s giant dinosaur puppets across the road on August 6, 2019 in Edinburgh, Scotland. Australian theatre company Erth presents their best-selling show Dinosaur’s Zoo as part of Underbelly’s Fringe programme. Featuring giant dinosaur puppets which walk, roar and blink like the real thing, Dinosaur’s Zoo is a perfect example of edutainment for children of all ages, taking place at the McEwan Hall every day of the Fringe at 11am. (Photo by Jeff J. Mitchell/Getty Images)

Ja Kang Song, 71, and Ja Hyun Su, 72, dive for shellfish and are the main breadwinners for their families. In South Korea, 45% of the diving women of Jeju are over the age of 70. Routinely diving to depths of 20m and staying under for an average of two to three minutes, the pressure on the body takes its toll and, like many others, burst eardrums have left Ja Hyun Su deaf. Each season, between seven and 10 women die diving the waters around Jeju Island. (Photo by Andy W. Langton/Age International)

A colourful morning sunrise on Christmas Eve at Victoria Tower on Castle Hill, West Yorkshire, England on December 24, 2017. The history of human activity on the Castle Hill goes back over 4000 years. The site was developed as an iron age hill fort, surrounded by defensive ditches and ramparts. In the Middle Ages there was a castle on the hill, of which the well remains. The present tower was built to commemorate Queen Victoria's Diamond Jubilee of 1897. (Photo by Charlotte Graham/ZUMA Wire/Rex Features/Shutterstock)