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)

People pose for a photo with certificates after swimming in the ocean for the 121st annual Coney Island Polar Bear Club's New Year's Day plunge at Coney Island beach in the Brooklyn borough of New York, New York, USA, 01 January 2024. (Photo by Sarah Yenesel/EPA)

People run into the sea at the beach of Scheveningen on New Year's Day, Scheveningen, Netherlands, 01 January 2023. The traditional New Year's dive was resumed after the two previous editions were canceled due to the corona crisis. (Photo by Remko de Waal/EPA/EFE/Rex Features/Shutterstock)

A man takes a photo of a radio antenna that's part of the Atacama Large Milimeter Array Observatory on March 12, 2013 at Llano de Chajnantor, about 43 miles (70 kilometers) from San Pedro de Atacama, Chile. The $1.5 billion ALMA facility, which had its official inauguration on March 13, is considered the world's most expensive ground-based observatory. (Photo by Felipe Trueba/EPA)

Japanese ornamental dolls (hina dolls) are displayed on the stone steps at Tomisaki shrine during the Katsuura Big Hinamatsuri festival in Katsuura city of Chiba prefecture on February 28, 2023. (Photo by Yuichi Yamazaki/AFP Photo)

Renee LeGrand, of Foothill Ranch, Calif., takes a picture among wildflowers in bloom Monday, March 18, 2019, in Lake Elsinore, Calif. About 150,000 people flocked over the weekend to see this year's rain-fed flaming orange patches of poppies lighting up the hillsides near Lake Elsinore, a city of about 60,000 residents. The crowds became so bad Sunday that Lake Elsinore officials closed access to poppy-blanketed Walker Canyon. By Monday the #poppyshutdown announced by the city on Twitter was over and the road to the canyon was re-opened. (Photo by Gregory Bull/AP Photo)

Jodie Ounsley who plays Fury in the British TV show Gladiators reacts after finishing the Women's Open Category race at the World Coal Carrying Championships in Ossett, West Yorkshire, England, Monday, April 21, 2025. (Photo by Jon Super/AP Photo)

Afghan child stands in front of a makeshift shelter after an earthquake in Gayan village, in Paktika province, Afghanistan, Friday June 24, 2022. A powerful earthquake struck a rugged, mountainous region of eastern Afghanistan early Wednesday, flattening stone and mud-brick homes in the country's deadliest quake in two decades, the state-run news agency reported. (Photo by Ebrahim Nooroozi/AP Photo)