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 girl washes the body paint off her arm on the shore of Lake Balaton during the coinciding Strand Festival and B.My.Lake Festival in Zamardi, 110 kms southwest of Budapest, Hungary, 24 August 2016. (Photo by Zoltan Balogh/EPA)

A girl poses at an entrance of her house next to a bomb dropped by the U.S. Air Force planes during the Vietnam War, in the village of Ban Napia in Xieng Khouang province, Laos September 3, 2016. From 1964 to 1973, U.S. warplanes dropped more than 270 million cluster munitions on Laos, one-third of which did not explode, according to the Lao National Regulatory Authority. (Photo by Jorge Silva/Reuters)

In this September 10, 2016 picture, a girl takes pictures of a fellow contestant while warming up backstage before competing in the Romania Miss Pole Dance Contest, ahead of the finals of the Pole Sport&Fitness World Championship 2016 in Bucharest, Romania. (Photo by Vadim Ghirda/AP Photo)

Airmen and their Japanese dates “do” the town together, visiting the local points of interest. Almost every community in Japan has it's famous shrines and parks. Tachikawa boasts beautiful environment. Girls are wearing western dress, May 1952. (Photo by National Archives and Records Administration)

A Yemeni soldier, pictured through a vehicle's windscreen, which was damaged by a bullet, gestures out of the window, in Marib, Yemen October 15, 2015. Marib is a city that is heavily armed even by the standards of Yemen, where the ready availability of weapons helped start civil war and is now preventing anyone coming out on top. Yemenis often say there are three guns for every person, a boast that has become an urgent concern in a country where the United Nations says the humanitarian situation is "critical". (Photo by Angus McDowall/Reuters)

A CIT guard carries his gun handgun while bringing a bag containing cash inside an armoured vehicle during a money collection in Johannesburg's CBD, on December 8, 2020. As the Christmas festive season approaches, cash-in-transit (CIT) companies are gearing up as they continue to be target of crime, with about 3000 money vans traveling daily nationwide. Despite the COVID-19 lockdown, there have been 260 cash-in-transit heist incidents in South Africa this year, with 19 CIT crew members killed. Cash-in-transit heists in the country are often military-style planned operations with criminals recurring to bomb making and assault rifles attacks. (Photo by Michele Spatari/AFP Photo)

Soldiers evacuate a hostage from a mass shooting scene at the Terminal 21 shopping mall in Nakhon Ratchasima, Thailand, 09 February 2020. According to media reports, at least 21 people were killed, and as many as 30 wounded after a Thai soldier, identified as 32-year-old Jakraphanth Thomma, went on a shooting rampage with a M60 machine gun in the city of Nakhon Ratchasima, also known as Korat. Thomma held an unknown number of people hostage within the Terminal 21 shopping mall for around 17 hours before being shot and killed in a police operation. (Photo by Rungroj Yongrit/EPA/EFE)