A mason bee deposits its collected pollen in an elderberry stick near Hessen, Germany on March 27, 2020. The food supply is sufficient for the eleven-month development of the brood from the egg to the finished bee. Wild bees are active in March and April and die before their offspring hatch. (Photo by Arne Dedert/dpa)

In this November 12, 2015, file photo, Mt. Everest is seen from the way to Kalapatthar in Nepal. An American climber has died near the summit of Mount Everest and an Indian climber is missing after heading down from the mountain following a successful ascent, expedition organizers said Sunday. (Photo by Tashi Sherpa/AP Photo)

A South Korean marine in action during their regular drill on Yeonpyeong Island, South Korea November 1, 2018. (Photo by Jeon Heon-Kyun/Pool via Reuters)

Mariana Sousa, student of the Ballet Paraisopolis, warms up during a rehearse in Paraisopolis favela, outskirts of Sao Paulo, Brazil on August 27, 2020, amid the new coronavirus COVID-19 pandemic. The 200 ballet students of Paraisopolis, the second largest favela in Sao Paulo, restarted rehearsals after five months with a coreography about a police operation that put their community in mourning last year. (Photo by Nelson Almeida/AFP Photo)

WrestlerTeddy Sheedi (L) fights his opponent during the traditional Sindhi Malakhra wrestling in Karachi, Pakistan, 13 December 2020. A Malakhra match begins with both wrestlers tying a twisted cloth around the opponent's waist. Each one then holds onto the opponent's waistcloth and tries to throw him to the ground. (Photo by Shahzaib Akber/EPA/EFE)

People wait for Pope Francis to celebrate mass at the Franso Hariri Stadium in Irbil, Kurdistan Region of Iraq, Sunday, March 7, 2021. The Vatican and the pope have frequently insisted on the need to preserve Iraq's ancient Christian communities and create the security, economic and social conditions for those who have left to return (Photo by Andrew Medichini/AP Photo)

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)