Cars drive under a rainbow near Bad Langensalza, Germany, Wednesday, November 2, 2016. (Photo by Jens Meyer/AP Photo)

Soldiers try to attach the balloon to their car, June 1944. (Photo by Jared Enos/Mediadrumworld.com)

Hostesses pose in front of a Suzuki Ignis car at the European Motor Show in Brussels, Belgium, January 13, 2017. (Photo by Francois Lenoir/Reuters)

A model poses with a motorcycle and a car on a racing track at the Essen Motor Show in Essen, Germany, November 27, 2015. (Photo by Ina Fassbender/Reuters)

A man looks at a car hit by a post after a tornado ripped through a neighbourhood in Havana, Cuba on January 28, 2019. (Photo by Fernando Medina/Reuters)

A car drives between trees in a small park in Frankfurt, Germany, Monday, April 8, 2024. (Photo by Michael Probst/AP Photo)

Cars drive on an alley between rape fields in the outskirts of Frankfurt, Germany, Monday, April 22, 2024. (Photo by Michael Probst/AP Photo)

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)