Muslim pilgrims pray around the holy Kaaba at the Grand Mosque, during the annual haj pilgrimage in Mecca September 30, 2014. (Photo by Muhammad Hamed/Reuters)

Dozens of crocodiles are seen in an inactive farm in the Jordan Valley near the Israeli Petzael settlement in the West Bank on January 18, 2021. Hundreds of crocodiles are stranded in a farm after an Israeli businessmen lost his business as Israel passed a law in 2012 defining the crocodile as a protected animal, and banning raising the animals for sale as meat or merchandise. (Photo by Menahem Kahana/AFP Photo)

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 hot air balloon floats over farm fields south of Washington, Ill., as the sun slips behind clouds on the autumn afternoon of Wednesday, September 24, 2014. (Photo by Ron Johnson/AP Photo/Peoria Journal Star)

Two holidaymakers amuse themselves with a porter's trolley whilst waiting for their train at Euston Station, London, 5th August 1939. (Photo by A. J. O'Brien/Fox Photos/Getty Images)

Racegoers in fashionable hats attend Ladies Day at Cheltenham Festival on March 15, 2017 in Cheltenham, England. (Photo by David Davies/PA Wire)