Participant rides a carousel at the women's-only Petrolettes motorcycle festival on July 21, 2018 in Milmersdorf, near Berlin in Germany. Around 300 bike women from across Europe come together for the third edition of the festival. Women connect their passion for high speed motorbikes with music, movies, races, yoga etc. Festival that goes for three days was initiated by a group of female motorbike riders called The Curves. (Photo by Maja Hitij/Getty Images)

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)