Students of the Krasnoyarsk choreographic college Anastasia Shevtsova (R) and Yulia Lyakhovykh do leg-splits as they study for an exam and a performance by the graduates at the State Theatre of Opera and Ballet, at the college's campus in the Siberian city of Krasnoyarsk, Russia, May 4, 2017. (Photo by Ilya Naymushin/Reuters)

A boy shoots a World War II machine gun armed with blanks at an weapon exhibition during a military show near Kirovsk, about 30 kilometers (19 miles) east of St. Petersburg, Russia, Sunday, January 21, 2018. (Photo by Dmitri Lovetsky/AP Photo)

Artist German Vinogradov acts in the performance of the burning of installation, devoted to Maslenitsa, or Pancake Week, a pagan holiday marking the end of winter, in the village of Nikola-Lenivets, Kaluga region, Russia, February 17, 2018. (Photo by Maxim Shemetov/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)

Stadium security stop a pitch invader during the UEFA EURO 2020 Group B football match between Finland and Belgium at Saint Petersburg Stadium in Saint Petersburg, Russia, on June 21, 2021. (Photo by Kirill Kudryavtsev/Pool via AFP Photo)

Sailors attend a memorial and funeral service for first rank captain Andrei Paliy, Russia's Black Sea Fleet deputy commander, who was killed in the eastern Ukrainian port city of Mariupol on March 20, in Sevastopol, Crimea on March 23, 2022. (Photo by Alexey Pavlishak/Reuters)

A Russian Su-35S combat aircraft and a Tu-95ms strategic bomber fly in formation above a church during a rehearsal for the flypast, which is part of a military parade marking the anniversary of the victory over Nazi Germany in World War Two, in Moscow, Russia on May 4, 2022. (Photo by Maxim Shemetov/Reuters)

A model displays a collection by graduates of the British Higher School of Art & Design during the Fashion Week at Zaryadye Park near Red Square in Moscow, Russia, Friday, June 24, 2022. (Photo by Alexander Zemlianichenko/AP Photo)