An Israeli soldier looks through her cell phone as she enjoys the Ranunculus flowers in a field in the southern Israeli Kibbutz of Nir Yitzhak, located along the Israeli- Gaza Strip border, during the Jewish holiday of Pesach (Passover) on April 12, 2017. (Photo by Menahem Kahana/AFP Photo)

The Pink Floyd inflatable pig floats next to Broadcasting House to promote their new exhibition at the V&A museum, in London, Britain May 10, 2017. (Photo by Neil Hall/Reuters)

A group of colorful row houses are reflected on to the top of a black car parked on 3600 block of N street in the Georgetown section of Washington DC, February 16, 2017. (Photo by John McDonnell/The Washington Post)

Commuters hang off a local passenger train in the morning in Colombo, Sri Lanka September 8, 2016. (Photo by Dinuka Liyanawatte/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)

A girl takes a nap during a Christmas eve mass at a Catholic church on the outskirts of Taiyuan, North China's Shanxi province, December 24, 2016. (Photo by Jason Lee/Reuters)

In this photo taken on Friday, July 14, 2017, a student at a paramilitary camp for children calls the rank to attention outside Kiev, Ukraine. As the deadly conflict in eastern Ukraine entered its third year, some parents in Ukraine are anxious to make sure their children are ready to fight it, instead of swimming and playing volleyball. (Photo by Efrem Lukatsky/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)