Clouds cover the sky over the Ernst-Taehlmann-Park housing estate after a thunderstorm in Berlin, Germany, Thursday, March 11, 2021. (Photo by Markus Schreiber/AP Photo)

Icelandic horses play in their paddock at a stud farm in Wehrheim near Frankfurt, Germany, as a mist rolls in on Thursday, August 5, 2021. (Photo by Michael Probst/AP Photo)

A regional train passes fog-covered fields in Wehrheim near Frankfurt, Germany, early Friday, October 7, 2022. (Photo by Michael Probst/AP Photo)

Icelandic horses feed on hay during a snow storm at a stud farm in Wehrheim near Frankfurt, Germany, Wednesday, December 14, 2022. (Photo by Michael Probst/AP Photo)

Germany's Darja Varfolomeev competes in the individual all-around final of the Olympic qualifier 40th FIG Rhythmic Gymnastics World Championships in Valencia on August 26, 2023. (Photo by Jose Jordan/AFP Photo)

Autumn colors border a road leading through a small valley near Blankenburg am Harz, Germany, Wednesday, November 1, 2023. (Photo by Matthias Schrader/AP Photo)

Netherlands and England fans arrive at the city ahead of a semi final match between Netherlands and England at the Euro 2024 soccer tournament in Dortmund, Germany, Wednesday, July 10, 2024. (Photo by Markus Schreiber/AP Photo)

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)