Tibetan pilgrims walk outside the Sera Monastery in Lhasa, Tibet Autonomous Region, China, 11 September 2016. Sera Monastery is known as one of the “great three” Gelug university monasteries of Tibet founded in 1419. (Photo by How Hwee Young/EPA)

These photographs are the work of urban explorer Dr Bradley Garrett who made headlines back in 2012 when he posted a series of snaps from the top of The Shard skyscraper while it was still under construction. Garrett, now a researcher at the University of Oxford, took these shots during his time with the London Consolidation Crew (LCC), a loose collection of urban explorers based in the English capital. Photo: Bradley Garrett stands on the edge of the Ritz-Carlton Chicago as lightning strikes in the distance in Chicago, US. (Photo by Bradley L. Garrett/Barcroft Media)

A pro-abortion activist wearing a poncho with an illustration of a woman in jail, demonstrates to demand the decriminalization of abortion in Mexico City, Mexico September 28, 2016. (Photo by Carlos Jasso/Reuters)

A workman sweeping the highest sidewalk in the world, the 81st story of the Empire State Building, the world's tallest building, to the top of which the greatest dirigible “Los Angeles” will attempt to moor, New York, New York, early 1930s. This photo was made 1,248 feet above street level. (Photo by Adam Glickman/Underwood Archives/Getty Images)

An extreme Vespa enthusiast rides his bike after attending weekend festival for extreme Vespas in Semarang, Central Java, Indonesia, July 22, 2018. Every year, Indonesians from teens and granddads, to mechanics and students, gather in eastern Java to celebrate their love of the iconic Italian Vespa scooter. (Photo by Darren Whiteside/Reuters)

Takahiro Shito, 47, and his wife Sayomi Shito, 46, pray with their children Tomoka, 14, and Kenya 16, and their great uncle Akinori Takahashi, 76, as they pay respects to their daughter Chisato,12, buried in a nearby cemetery, victim of the Okowa Elementary School tragedy, who was killed during last year's tsunami on March 11, 2012 near Ishinomaki, Japan. Teachers at the school weren't trained for tsunami evacuation and didn't to lead the children up the snow covered mountain behind the school after the tsunami warning was sounded. Out of 108 students at the school, 74 died and four remain missing; 10 of the school's 13 teachers were also killed. (Photo by Daniel Berehulak /Getty Images)

A rescue worker holds an injured boy after what activists said were airstrikes carried out by the Russian air force in Idlib city, Syria December 20, 2015. (Photo by Ammar Abdullah/Reuters)

Engine driver Josef Kowatsch (top L) steers a train through the NEAT Gotthard Base Tunnel during a media visit near the town of Erstfeld August 24, 2015. Crossing the Alps, the world's longest train tunnel should become operational at the end of 2016, consisting of two parallel single track tunnels, each of a length of 57 km (35 miles). (Photo by Arnd Wiegmann/Reuters)