A reveler takes part in the 19th Gay Pride Parade at downtown Caracas, Venezuela on June 30, 2019. (Photo by Federico Parra/AFP Photo)

Dario Sammartino, of Italy, competes at the final table during the World Series of Poker at the Rio hotel-casino in Las Vegas Sunday, July 14, 2019. (Photo by Steve Marcus/Las Vegas Sun via AP Photo)

“The Supercell”. This shortlisted image by Dennis Oswald Huge farmland of was taken in south-west Oklahoma, US. (Photo by Dennis Oswald/2019 Weather Photographer of the Year/RMetS)

An Extinction Rebellion activist takes part in a protest in Berlin, Germany on October 5, 2020. (Photo by Michele Tantussi/Reuters)

Majesty Davis, 3, cries while visiting Santa Claus, who sits behind a plexiglass divider due to the coronavirus disease (COVID-19) pandemic, at the Willow Grove Park Mall in Willow Grove, Pennsylvania, U.S. November 14, 2020. (Photo by Mark Makela/Reuters)

Russian President Vladimir Putin speaks via video call during a news conference in Moscow, Russia, Thursday, December 17, 2020. This year, Putin attended his annual news conference online due to the coronavirus pandemic. (Photo by Alexander Zemlianichenko/AP Photo)

Mortuary workers take off their protective clothing at the entrance of a building decorated with a Christmas tree, after removing the body of person who allegedly died of COVID-19 in Barcelona, Spain, Wednesday, December 23, 2020. (Photo by Emilio Morenatti/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)