Urban photographer Roman Robroek spent five years scouring the continent for the grandest examples of forgotten architectural beauty. Here: Watch your step on this Polish spiral staircase. (Photo by Roman Robroek/South West News Service)

Two hippopotamus are fed with pumpkins at the Hanoi Zoo, in Hanoi, Vietnam, 25 October 2018. The zoo has been the home for more than 800 animals of over 90 different species, including three hippopotamus, since it was built in 1976. (Photo by Luong Thai Linh/EPA/EFE)

13-year-old Emmanuel Festo from Tanzania poses for a portrait with a plush toy that he says makes him feel safe at night and that he sleeps with, in New York's Staten Island, September 21, 2015. Albino body parts are highly valued in witchcraft and can fetch a high price. Superstition leads many to believe albino children are ghosts who bring bad luck. Some believe the limbs are more potent if the victims scream during amputation, according to a 2013 United Nations report. (Photo by Carlo Allegri/Reuters)

A 20 metre high spiral staircase in a tower used as an emergency exit, is seen inside a Federal Reserve bank (Bundesbank) bunker, prior to the bunker's official opening to the public in Cochem, Germany, March 18, 2016. West Germany's Central Bank (Deutsche Bundesbank) stored some 20 billion German marks of emergency notes in two underground bunkers, one in Frankfurt the other in Cochem, between 1964-1988 during the cold war. (Photo by Kai Pfaffenbach/Reuters)

Anthony Joshua punches Kubrat Pulev during the IBF, WBA, WBO and IBO World Heayweight Title fight between Anthony Joshua and Kubrat Pulev at The SSE Arena, Wembley on December 12, 2020 in London, England. A limited number of fans (1000) are welcomed back to sporting venues to watch elite sport across England. This was following easing of restrictions on spectators in tiers one and two areas only. (Photo by Andrew Couldridge – Pool/Getty Images)

Members of South Korean K-Pop girl group Brave Girls pose on the red carpet at KCON Seoul 2022 in Seoul on May 7, 2022. (Photo by Anthony Wallace/AFP Photo)

A painted figure is seen on a wall of the home of the mother of Robert E. Crimo III, the 21-year-old suspect facing seven counts of first-degree murder in an attack on a Fourth of July parade, in Highland Park, Illinois, U.S. July 6, 2022. (Photo by Cheney Orr/Reuters)

A customer plays “Red Light, Green Light” game from the Netflix show “Squid Game” at Strawberry Cafe in Jakarta, Indonesia, October 15, 2021. (Photo by Ajeng Dinar Ulfiana/Reuters)