Russian servicemen stand next to a Russian Yars RS-24 intercontinental ballistic missile system before a rehearsal for the Victory Day parade, with the Moscow International Business Center also known as “Moskva-City” seen in the background, at a range in Moscow, Russia, May 5, 2016. (Photo by Maxim Shemetov/Reuters)

Druids, pagans and revellers cheer as the sun rises at Stonehenge on December 22, 2011 in Wiltshire, England. The unseasonable warm weather encouraged a larger than normal crowd to gather at the famous historic stone circle to celebrate the sunrise closest to the Winter Solstice, the shortest day of the year. (Photo by Matt Cardy/Getty Images)

In this photograph taken on July 7, 2018, an Indian Buddhist monk plays with the wind amongst prayer flags on a hill overlooking Tnagyud Gompa monastery in Komik in Spiti Valley in the northern state of Himachal Pradesh. (Photo by Xavier Galiana/AFP 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)

Parent hedgehogs Maria, left, and Gosha, 2nd right, eat with their albino babies in a private Zoo in Moscow, Russia, Thursday, August 22, 2013. Three rare albino hedgehog babies, born on the same day as Britain's new prince, have moved into a miniature castle at a Moscow petting zoo. The three are named after the Prince of Cambridge – George, Alexander and Louis. On Thursday, when they turned one month old, they were shown their new home at the All-Russia Exhibition Center. (Photo by Alexander Zemlianichenko Jr./AP Photo)

Russia's Alexandra Stepanova and Ivan Bukin perform during the ice dance free dance program at the Rostelecom Cup ISU Grand Prix of Figure Skating in Moscow November 15, 2014. (Photo by Grigory Dukor/Reuters)

Flashmob: Water Battle on All-Russian Exhibition Center in Moscow, Russia, on August 5, 2012. (Photo by Lilja Dal)

“Aquarium or Akvarium (Russian: Аквариум) is a Russian rock group, formed in Leningrad in 1972 by Boris Grebenshchikov (Борис Гребенщиков), then a student of Applied Mathematics at Leningrad State University, and Anatoly (George) Gunitsky, then a playwright and absurdist poet”. – Wikipedia