A round circle of smoke coming from the mouth of the Etna volcano is seen in the sky during an eruption on the southern Italian island of Sicily April 11, 2013. Mount Etna is Europe's tallest and most active volcano. (Photo by Antonio Parrinello/Reuters)

“Diver in Magic Kingdom”. Green Lake (Grüner See) is located Tragöss Austria. In spring snowmelt raises the lake level about 10 meters. This phenomenon, which lasts only a few weeks covering the hiking trails, meadows, trees. The result is magical to watch diving landscapes. Photo location: Grüner See at Tragöss, Austria. (Photo and caption by Marc Henauer/National Geographic Photo Contest)

A tour group wanders through block 7 of Eastern State Penitentiary in Philadelphia, Pennsylvania April 30, 2014. Opened in 1829, with the original corrective system of “confinement in solitude with labor”, the penitentiary housed about 75,000 inmates in its 142 years of operation. At Eastern State reunions, former inmates, staff and guard gather to share memories and trade stories and get a chance to describe their experiences in question-and-answer sessions with the public. (Photo by Mark Makela/Reuters)

Participants dressed as Santa Claus take part in the Great Edinburgh Santa Run on December 11, 2011 in Edinburgh, Scotland. Around a thousand people took part in the annual fundraising event, with all money raised being donated to the charity “When You Wish Upon a Star”. (Photo by Jeff J. Mitchell/Getty Images)

A man walks on the Cobb as storm waves break behind on December 13, 2011 in Lyme Regis, England. (Photo by Matt Cardy/Getty Images)

“In beard and hat”; Udine, Friuli-Venezia Giulia, Italy, 2013. (Photo by Giulio Magnifico)

Earlier this year, Belgian film-maker and artist Vincent Bal stumbled upon an uncanny resemblance to an elephant in the shadow of his tea cup. This gave him the idea for Shadowology, a series of doodles that interact with the shadows of simple, everyday objects: a banknote, some ice cubes and a flower, for example, can turn into a church, a woman and a hippy. “I draw a few lines and I get my image. It’s really the shadows that inspire me”, Bal says. Here: “Stonedog”. (Photo by Vincent Bal/The Guardian)

Patrick Fellows #21, Allan McShane #26, Carson Edwardson #8 and Shaun Bily #23 of the Erie Otters sit on the bench during the first period of an OHL game against the Niagara IceDogs at the Meridian Centre on October 6, 2016 in St Catharines, Ontario, Canada. (Photo by Vaughn Ridley/Getty Images)