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 Santa Claus taking a selfie on a surfboard is seen in the yard of a home in the Sleepy Hollow area of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. (Photo by Lucy Nicholson/Reuters)

A deer forages for food in the early morning sun as cooler temperatures bring on the autumn season at Dunham Massey on on October 11, 2010 in Lymm, England. Shortening daylight hours and cooler weather brings on the rutting season for Red and Fallow deer herds and Autumn foliage colours across Britain. (Photo by Christopher Furlong/Getty Images)

A red deer stag watches from the cover of a bracken thicket during the autumn rutting season at Richmond Park on October 10, 2011 in London, England. Autumn sees the start of the “Rutting” season where the stags and bucks bellow in an attempt to attract female does and hinds. (Photo by Dan Istitene/Getty Images)

Civilians present their rations cards in order to receive humanitarian food aid being distributed by the Iraqi Red Crescent, in the eastern side of Mosul, Iraq, Tuesday, January 31, 2017. Iraqi forces declared Mosul's eastern half fully liberated, just over three months after the operation to retake the city from IS was formally launched in October. (Photo by Khalid Mohammed/AP Photo)

People look at smoke and flame rising from the Nevskaya Manufaktura textile factory founded by English merchant J. Thornton in 1841, in St. Petersburg, Russia, Monday, April 12, 2021. The emergencies ministry said the fire had broken out over several floors of the red-brick Nevskaya Manufaktura building on the Oktyabrskaya Embankment of the Neva River. (Photo by Dmitri Lovetsky/AP Photo)