“Ashes and Snow by Canadian artist Gregory Colbert is an installation of photographic artworks, films, and a novel in letters that travels in the Nomadic Museum, a temporary structure built exclusively to house the exhibition. The work explores the shared poetic sensibilities of human beings and animals”. – Wikipedia. (Photo by Gregory Colbert)

Beneath the Swedish capital lies an intricate web of underground train lines. More than 90 of the 100 stations in the 110km tunnel system, sometimes referred to as “the world’s longest art gallery”, have been decorated with paintings, installations, mosaics and sculptures by 150 artists since the 1950s. After spending a couple of weeks exploring arctic Norway and Sweden, London-based travel photographer Conor MacNeill headed underground to capture images of the metro stations. Here: A rainbow arcs over a girl on the platform of Stadion station. (Photo by Conor MacNeill/The Observer)

A demonstrator argues with policewomen after she turned up her shirt and was taken out from a protest to demand the resignation of Brazilian President Dilma Rousseff, on March 13, 2016 in Paulista Avenue in Sao Paulo. Protesters, many draped in the Brazilian national flag, poured into the streets of Brasilia and Rio de Janeiro on Sunday at the start of mass demonstrations seeking to bring down President Dilma Rousseff. Authorities in Sao Paulo, Brazil's biggest city and an opposition stronghold, said they were bracing for a million protesters. (Photo by Miguel Schincariol/AFP Photo)

Elderly people attend an aquatic exercise at a private pool in Bangkok, Thailand, April 28, 2016. Many Thai families look after elderly relatives at a cost that countrywide adds up to just under a third of household income. The number of families facing this issue will balloon as the population ages at a rate among the fastest in Southeast Asia. (Photo by Athit Perawongmetha/Reuters)

Homeless man Alonzo Harrison, 47, takes a nap on a bench at Pershing Square decorated with Christmas lights in the background on Monday, December 4, 2017, in Los Angeles. A homeless crisis of unprecedented proportions is rocking the West Coast, and its victims are being left behind by the very things that mark the region's success: soaring housing costs, rock-bottom vacancy rates and a roaring economy that waits for no one. (Photo by Jae C. Hong/AP Photo)

Somali couple Mohamed Noor (L) and Huda Omar pose for a photograph at their makeshift home during their wedding ceremony in Mogadishu's Rajo camp, Somalia August 17, 2016. Having met two years ago, the pair have just married at Rajo camp, where some 400 families live. Most, like Noor's parents, came here in the early 1990s to flee famine. (Photo by Feisal Omar/Reuters)

Dajana Djuric, 25, who has worked as a chimney sweep since the age of six, cleans a chimney in Brcko, Bosnia and Herzegovina. Dajana Djuric, believed to be the only female chimney sweep in Bosnia and Herzegovina, has to contend with perilous roofs in the depth of winter. (Photo by Dado Ruvic/Reuters)