A woman walks inside a building in downtown Havana, Cuba April 21, 2016. (Photo by Alexandre Meneghini/Reuters)

Participants dance and climb on an art installation as approximately 70,000 people from all over the world gather for the 30th annual Burning Man arts and music festival in the Black Rock Desert of Nevada, U.S. August 31, 2016. (Photo by Jim Urquhart/Reuters)

American stand-up comedian and actress Whitney Cummings fools around with photographers after she, Griffin Johnson, and Josh Richards have dinner together at Craig's in West Hollywood, CA. on April 6, 2021. (Photo by Backgrid USA)

A monument with old MiG fighter jet is seen next to a damaged civil infrastructure building at the site of a Russian military strike, as Russia's attack on Ukraine continues, in Vinnytsia, Ukraine on July 14, 2022. (Photo by Valentyn Ogirenko/Reuters)

Benfica's Portuguese forward Goncalo Ramos (R) vies with Portimonense's Japonese goalkeeper Kosuke Nakamura (L) during the Portuguese League football match between SL Benfica and Portimonense SC at Luz stadium in Lisbon on January 6, 2023. (Photo by Patrícia de Melo Moreira/AFP Photo)

Two white storks stand close to each other on their nest on a tree in Zerbolo, Italy, Thursday, October 26, 2017. (Photo by Antonio Calanni/AP Photo)

A column of sand and front of clouds are seen by dash cam as the car drives near a tornado in Dragalina, Calarasi county, Romania April 30, 2019 in this still image taken from a video obtained from social media. (Photo by Alexandra Puscasu via Reuters)

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)