Six new Canadians take their oath of citizenship while harnessed on the CN Tower's “Edgewalk” 356 metres (1,168 feet) above Toronto, Ontario, Canada in a still image from video October 9, 2018. (Photo by CN Tower/Handout via Reuters)

A protester sprays paint on the window of a bank during a rally against Expo 2015 in Milan, Italy, April 30, 2015. The Milan Expo will open in the city on May 1. Officials are counting on some 20 million visitors to the six month-long exhibition of products and technologies from around the world. (Photo by Stefano Rellandini/Reuters)

Seehund “Bruno” looks out of his transport box before making his way to the water on the beach of the island of Juist, Germany on August 14, 2013. Four young seals were released after six weeks of recovery at a rescue station in Norden-Norddeich. (Photo by Carmen Jaspersen/AFP Photo/DPA)

People enjoy their time during the last day of the Dubai Expo 2020 in Dubai, United Arab Emirates, Thursday, March 31, 2022. The world's fair in Dubai, the pandemic-delayed Expo 2020, closed on Thursday after six months of concerts, conferences and festivities. (Photo by Ebrahim Noroozi/AP Photo)

Six year old Gillian Smith preparing for the All England Stage Dancing Competition where she has previously won five certificates and a silver medal in the under sevens category. (Photo by Terry Fincher/Keystone/Getty Images). 5th July 1957

The Messner Mountain Museum (MMM) Corones, designed by the renowned Iraqi-British architect Zaha Hadid, is the final instalment in a series of six mountain-top museums curated by Reinhold Messner, the Italian mountaineer known for making the first ascent of Mount Everest without supplemental oxygen.

Three Chinese soldiers at the time of a civil war in China. (Photo by General Photographic Agency/Getty Images). 1922

A man dressed as the “Star Wars” character Darth Vader sits on a bench in central Lviv, Ukraine, November 24, 2016. (Photo by Gleb Garanich/Reuters)