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 peacock leaps into the air as it battles a rival over territory on a foggy morning. The brightly coloured bird jumped almost six feet into the air before crashing down on its opponent. The fight was captured by amateur photographer Nilesh Patel, in Dudhwa National Park, India. (Photo by Nilesh Patel/Solent News & Photo Agency/Solent News)

Israelis sit by as a man poses while jumping into the pool of the natural water spring of Ein al-Faraah near the Palestinian village of Doura, west of Hebron in the occupied West Bank, during the Jewish religious holiday of Sukkot (Feast of the Tabernacles) on October 17, 2019. (Photo by Hazem Bader/AFP Photo)

Female members of the Hammer tribe from the village of Turmi, situated in southern Ethiopia near the Kenyan border, dance as part of a ritual called the “bull jumping ceremony” that takes place during the passage of a young boy to adulthood, in Turmi, Ethiopia, 25 September 2019. (Photo by Stéphanie Lecocq/EPA/EFE)

Iberian lynx Mistral jumps in a field after being released by Portugal's Minister of Environment Joao Matos Fernandes (unseen) and others in the Mount Milhouro (Herdade da Cela) region in Mertola, Portugal, 13 May 2016. Mistralis the 18th lynx bred in captivity released since late 2014. (Photo by Nuno Veiga/EPA)

A competitor tries to clear a jump during the RHL Beach Race at Weston-Super-Mare on October 9, 2011 in Weston-Super-Mare, England. (Photo by Richard Heathcote/Getty Images)

A topless Femen activist jumps on the car carrying former IMF chief Dominique Strauss-Kahn (not seen) as he arrives for his trial in Lille, northern France, on February 10, 2015. Three topless women from the protest group Femen jumped on the car of Dominique Strauss-Kahn as the former IMF chief arrived to testify at his trial for “aggravated pimping”. With slogans scrawled on their half-naked bodies and hurling insults at the car, the three protesters were quickly rounded up by police as the car entered an underground parking area. (Photo by Denis Charlet/AFP Photo)