Portuguese driver Ricardo Poremi and co-driver Jorge Monteiro ride during a session on the eve of technical checkup in Jeddah, on December 31, 2020 ahead of the 2021 Dakar Rally, which this year will take place in Saudi Arabia from January 3 to 15, 2021. (Photo by Franck Fife/AFP Photo)

Students run out of their school celebrating their high school graduation at Nacka Gymnasium following the spread of the corona virus disease (COVID-19) in Stockholm, Sweden, June 3, 2020. (Photo by Jessica Gow/TT News Agency via Reuters)

Cars slowly move along a bridge in traffic jam in central Moscow, Russia on December 11, 2018. (Photo by Yuri Kadobnov/AFP Photo)

Canadian singer-songwriter Shania Twain poses for a selfie as she attends the 2022 People's Choice Awards in Santa Monica, California, U.S. December 6, 2022. (Photo by Mario Anzuoni/Reuters)

A visitor looks at pictures of French photographer Jacques-Henri Lartigue (1894-1986), on July 1, 2013 during the 44thd annual Rencontres d'Arles photography festival in Arles, southern France. The event runs until September 22. (Photo by Boris Horvat/AFP Photo)

A sign is posted in front of the new Yoga Room at San Francisco International Airport's terminal two on January 26, 2012 in San Francisco, California. (Photo by Justin Sullivan/Getty Images)

SpaceX’s Dragon spacecraft, March 6, 2014. SpaceX's Falcon 9 rocket and Dragon spacecraft launched from Launch Complex 40 at the Cape Canaveral Air Force Station, Florida, for their third official Commercial Resupply (CRS) mission to the orbiting lab on April 18, 2014. Dragon returned to Earth with a parachute-assisted splashdown off the coast of southern California on May 14, 2014. Dragon is the only operational spacecraft capable of returning a significant amount of supplies back to Earth, including experiments. (Photo by Ron Lin/SpaceX Photos)

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)