An arial view of Top Pearsy's Maize Maze in the shape of Harry Potter, on July 11, 2011 in York, England. Farmer Tom Pearcy has cut two portraits of Harry Potter in his crop of maize plants. With some subtle differences the two images create the world's largest spot the difference competition. At over 50m in diameter, and cut out of over 1 million living maize plants, the York Maze is the largest “Maize Maze” in Europe and one of the largest in the world. (Photo by Bethany Clarke/Getty Images)

A visitor tries out the new glass Skywalk at the top of the refurbished Blackpool Tower on September 1, 2011 in Blackpool, England. After a GBP Ј20 million refurbishment, the iconic seaside Blackpool Tower opened today to the general public. The observation deck at the top of the tower becomes the Blackpool Tower Eye and features a skywalk made of glass overlooking the sea and the promenade. The opening is part of Blackpool's GBP Ј250 million GBP regeneration project. (Photo by Christopher Furlong/Getty Images)

Swiss police officers stand beside of mock gates of the NEAT Gotthard Base Tunnel inside the event hall for the upcoming opening ceremony near the town of Erstfeld, Switzerland May 31, 2016. The celebrations of the opening of the Gotthard Base Tunnel will start on June 1, 2016. With a length of 57 km (35 miles) crossing the Alps, the Gotthard Base tunnel is the world's longest train tunnel. (Photo by Arnd Wiegmann/Reuters)

Performers dressed as Pikachu, a character from Pokemon series game titles, march during the Pikachu Outbreak event hosted by The Pokemon Co. on August 9, 2017 in Yokohama, Kanagawa, Japan. A total of 1, 500 Pikachus appear at the city's landmarks in the Minato Mirai area aiming to attract visitors and tourists to the city. The event will be held through until August 15. (Photo by Tomohiro Ohsumi/Getty Images)

“Grit and Glamour”, a retrospective of the late British photographer Elsbeth Juda, who fled Nazi occupation and came to England in 1933, is at the Jewish Museum, in London, until July 1, 2018. Here: Shelagh Wilson, Copacabana beach, Rio de Janeiro, 1951. (Photo by Elsbeth Juda Archive/Victoria and Albert Museum)

Young artists perform at the presentation of clowns in a hall of the Arts Palace during the first clown festival in Belarus in Bobruisk, some 150 km from Minsk, Belarus, 01 April 2018. About 60 clowns from Belarus and Russia gathered to entertain spectators. For 1 day Bobruisk became a capital of Jokes and Humour. Theaters of clownery, mime-theaters, individual performers of humorous genre, stilts and hospital clowns performed on a stage of the Palace of Arts. (Photo by Tatyana Zenkovich/EPA/EFE)

Performers dressed as Pikachu, a character from Pokemon series game titles, march during the Pikachu Outbreak event hosted by The Pokemon Co. on August 10, 2018 in Yokohama, Kanagawa, Japan. A total of 1, 500 Pikachus appear at the city's landmarks in the Minato Mirai area aiming to attract visitors and tourists to the city. The event will be held through until August 16. (Photo by Tomohiro Ohsumi/Getty Images)

In this September 1, 2014 photo released by the U.S. Geological Survey, fluid lava streams from the June 27 lava flow from the Kilauea volcano in Pahoa, Hawaii. The June 27 lava flow is named for the date it began erupting from a new vent. The Hawaiian Volcano Observatory issued a warning Thursday, September 4, 2014 to a rural community in the path of a lava flow on Hawaii's Big Island, as the molten rock moved to within a mile of homes. Observatory scientists said lava from the Kilauea volcano could reach the Kaohe Homesteads in five to seven days if it continues advancing through cracks in the earth. (Photo by AP Photo/U.S. Geological Survey)