An East German civilian (L) shows an East German customs officer the contents of his Trabant (auto) at checkpoint Potsdamer Platz in East Berlin in this November 24, 1989 file picture, as East Germany enforcing stringent customs controls to avoid smuggling. (Photo by Reuters)

Residents gather to watch fireworks rehearsals ahead of the upcoming 100th anniversary of the founding of China's ruling Communist Party in Beijing on Tuesday, June 22, 2021. Chinese authorities have closed Beijing's central Tiananmen Square to the public, eight days ahead of a major celebration being planned to mark the 100th anniversary of the founding of the ruling Communist Party. (Photo by Ng Han Guan/AP Photo)

Members of the Colombian Military forces pray for members of the military that have lost their lives and peace in the country at the Military Engineers School in Bogota, Colombia on October 14, 2021. (Photo by Juancho Torres/Anadolu Agency via Getty Images)

A girl swings on a rope swing over the Volga River in Zavolzhsk, Ivanovo Region, Russia on June 9, 2020. (Photo by Vladimir Smirnov/TASS)

A Syrian refugee girl cries as she walks through a rainstorm towards Greece's border with Macedonia, near the Greek village of Idomeni, September 10, 2015. Most of the people flooding into Europe are refes fleeing violence and persecution in their home countries who have a legal right to seek asylum, the United Nations said on Tuesday. (Photo by Yannis Behrakis/Reuters)

German flying ace Baron Manfred von Richthofen (1892–1918) also known as The Red Baron with his dog Moritz, circa 1916.

Fog hangs between pine trees in a forest near Neubrueck, eastern Germany, on November 20, 2012. Meteorologists forecast cloudy sky and temperatures around 5 degrees Celsius for the region. (Photo by Patrick Pleul/AFP Photo)

A woman visits a room in a house built upside-down in Russia's Siberian city of Krasnoyarsk, December 14, 2014. The house was constructed as an attraction for local residents and tourists. (Photo by Ilya Naymushin/Reuters)