Stunning silhouettes under European cities reveal the size and splendor of the continent’s urban foundations. Photographer and content-manager Anna Arinova, 28, from Moscow, captured the awe-inspiring labyrinths in Russia and Germany. Here: Regenwurmlager, Poland. The Regenwurmlager is an extensive underground fortification area constructed by Germany in 1920s-1940s, now in western Poland, near the city of Międzyrzecz. (Photo by Anna Arinova/Caters News)

A child plays the ice slide at the Ice-Snow World park in Harbin, capital of northeast China's Heilongjiang Province, January 5, 2017. The theme park which used about 330,000 cubic meters of ice and snow for construction opened on Thursday. (Photo by Xinhua/Barcroft Images)

Jim Mahoney looks out from his yard towards the construction of the Foxconn manufacturing complex, after he and his wife Kim refused to sell their home and property to Foxconn, in the Racine County city of Mt. Pleasant, Wisconsin, U.S., July 27, 2019. (Photo by Brian Snyder/Reuters)

A Palestinian woman argues with an Israeli border policewoman over the Israeli demolition of a building housing an apartment and a restaurant as the building owners said they were informed by the forces that they did not obtain a construction permit, in Beit Jala in the Israeli-occupied West Bank on August 26, 2019. (Photo by Mussa Qawasma/Reuters)

Children play football on March 10, 2022 on a concrete slab in Mukuru Kwa Njenga informal settlements, where structures have been demolished in November 2021 to pave the way for the construction of the Nairobi Expressway. (Photo by Simón Maina/AFP Photo)

Sierra “Lovely Amazin” Redd of Greensboro, North Carolina, poses for bikers by a custom Suzuki Katana on Ocean Boulevard during the 2015 Atlantic Beach Memorial Day BikeFest in Myrtle Beach, South Carolina May 24, 2015. (Photo by Randall Hill/Reuters)

This picture taken on September 9, 2014 shows a waiteress handing over food to customers at a prison themed restaurant in Tianjin. As more themed restaurants are popular in China, a “prison style” restaurent in Tianjin is aimed at reminding people to observe the law and to be good citizens. (Photo by Wang Zhao/AFP Photo)

An Egyptian boy holds a camel at the Berqash camel market northeast of Cairo, on August 17, 2018. Muslims across the world are preparing for the Eid al-Adha holiday when custom requires the faithful to make a sacrifice. (Photo by Khaled Desouki/AFP Photo)