Inmates ride in a bus out of the Cojutepeque prison in El Salvador, Thursday, June 16, 2016. This prison, which houses more than a thousand 18th street imprisoned gang members, will be closed down by the government, since it has been unable to prevent the amount of illegal activities happening inside the prison walls. Inmates will be relocated to other medium-security prisons. (Photo by Salvador Melendez/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)

A Chicago Police Officer runs toward gunfire as looters break into downtown stores in the early hours of the morning on August 10, 2020. (Photo by RMV/Rex Features/Shutterstock)

A racegoer reacts to picking a winner in the first race on the third day of the Royal Ascot horserace meeting, which is traditionally known as Ladies Day, at Ascot, England Thursday, June 17, 2021. (Photo by Alastair Grant/AP Photo)

A customer plays “Red Light, Green Light” game from the Netflix show “Squid Game” at Strawberry Cafe in Jakarta, Indonesia, October 15, 2021. (Photo by Ajeng Dinar Ulfiana/Reuters)

A woman wearing a protective mask walks through a platform of a train station during the afternoon rush hours as the Omicron variant continues to spread, amid the coronavirus disease (COVID-19) pandemic, in Jakarta, Indonesia, January 3, 2022. (Photo by Willy Kurniawan/Reuters)

A street merchant waits for customers in Niamey, Niger, Monday, August 14, 2023. Niger's mutinous soldiers say they will prosecute deposed President Mohamed Bazoum for “high treason” and undermining state security. (Photo by Sam Mednick/AP Photo)

Plumes of smoke rise from the snow covered volcano Villarrica, in Pucon, Chile on December 7, 2023. (Photo by Cristobal Saavedra Escobar/Reuters)