Residents watch volcanic smoking and ashes rising from Mount Sinabung during an eruption in Karo, North Sumatra, Indonesia, February 24, 2016. Authorities have repeatedly called on local residents to remain patient in dealing with the impact of Sinabung's eruptions, which some experts have predicted will continue for five more years. (Photo by Xinhua/Barcroft Media)

A vendor drinks water as she waits for customers at a roadside flower market in Ahmedabad, India, February 8, 2017. (Photo by Amit Dave/Reuters)

Models wait for their turn at an audition for the upcoming Lakme Fashion Week (LFW) Summer/Resort 2017 in Mumbai, India, 14 December 2016. Around 83 national and international models participated in the audition from which five got selected. The LFW Summer/Resort 2017 is scheduled to start from 01 to 05 February 2017. (Photo by Divyakant Solanki/EPA)

A police officer stands at a police cordon near the scene of a terror attack in London, U.K., on Sunday, June 4, 2017. A van swerved into Saturday-night crowds on London Bridge, before three men got out and went on a stabbing rampage through nearby bars. (Photo by Luke MacGregor/Bloomberg)

A man wearing a traditional Russian costume holds a goose after a traditional goose fight during celebrations of Maslenitsa, also known as Pancake Week, which is a pagan holiday marking the end of winter, in Suzdal, Russia on February 29, 2020. (Photo by Maxim Shemetov/Reuters)

An indigenous woman looks on during the Terra Livre (Free Land) camp, a protest-camp to defend indigenous land and cultural rights that they say are threatened by the right-wing government of Brazil's President Jair Bolsonaro, in Brasilia, Brazil on April 4, 2022. (Photo by Adriano Machado/Reuters)

A child plays with a cat next to a makeshift animal shelter at Cihangir neighbourhood in Istanbul, Turkey, Thursday, March 23, 2023. Turan comes every single day with cat food in his hand to the makeshift shelter he helped build with the other volunteers in the area and takes care of the needs of the cats that reside their every single day. (Photo by Francisco Seco/AP 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)