To an outsider, their passion is at times illegal and often on the verge of life and death. But climbing rooftops of high-rise buildings and exploring abandoned facilities is in the blood of these young Muscovites. The small group calls itself “Rudex”, which stands for “roof and decay exploration”, and is akin a Western youth craze known as urbex or “urban exploration” of man-made structures. Here: Urban explorer Vad Him of Rudex team jumps whilst on a rooftop in Moscow, Russia, August 14, 2017. (Photo by Maxim Shemetov/Reuters)

A tourist train is decorated with Christmas lights in Bogotá, Colombia on December 10, 2017. (Photo by Jaime Saldarriaga/Reuters)

Revellers enjoy themselves during Hogmanay celebrations in Edinburgh, Scotland on December 31, 2017. (Photo by Russell Cheyne/Reuters)

Visitors wear traditional hanbok dress as they walk on the grounds of the Gyeongbokgung Palace after a snowfall in Seoul on January 17, 2022. (Photo by Anthony Wallace/AFP Photo)

Kim Yelim, of South Korea, competes in the women's free skate program during the figure skating competition at the 2022 Winter Olympics, Thursday, February 17, 2022, in Beijing. (Photo by Natacha Pisarenko/AP Photo)

The Milky Way rising above Durdle Door in Dorset, United Kingdom on Saturday night, March 18, 2023. The image consists of 19 two-minute exposures, ten of the foreground and nine of the sky which needed a motorised star tracker to ensure the Milky Way wasn't blurry. All the photos were merged together to reveal more detail than what the naked eye can see. (Photo by Nick Bull/Picture Exclusive)

A woman wades throug a flooded Main Street as she makes her way to work in Carrigaline, Co. Cork, Ireland on October 18, 2023. (Photo by David Creedon/The Irish Times)

Serra da Aboboreira Megalithic Set (Meninas do Crasto) on September 24, 2023 in Baiao, Portugal. Since 1978 that Serra da Aboboreira (Aboboreira Mountains) has been the scene of a systematic study of its archeological values, among which are the monuments known as megalithic. These are funerary monuments designing the landscape. These dolmens were constructed with stones (lithos) of medium or large dimensions (mega), which were laid in a, more or less, vertical position. Over these, it was still placed a lid, also of stone. These containers were covered by an artificial mound of earth and stones (dolmen). (Photo by Octavio Passos/Getty Images)