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)

The German Society for Nature Photography (GDT) has selected its Nature Photographer of the Year 2020. Here: Winner, Other animals. Jens Cullmann – Danger in the Mud. Crocodile in a drying pool. (Photo by Jens Cullmann/2020 GDT Nature Photographer of the Year)

Indian passengers travel on a local train in New Delhi, India, October 2017. Constructed in 1975 to bypass the crowded and passenger-heavy Old Delhi, New Delhi and Hazrat Nizamuddin railway stations, the railway line once used to be the lifeline of the capital. (Photo by Ankur Dutta/Barcroft Media)

Topless activist Kaila J. walks through the rain following a “Free the Nipple” demonstration in Hampton Beach, New Hampshire August 23, 2015. (Photo by Brian Snyder/Reuters)

Police officers wield their batons against activists from various student unions during a protest march demanding jobs and better education facilities, in Kolkata, India, February 11, 2021. (Photo by Rupak De Chowdhuri/Reuters)

A handout photo provided by the Police department in Lippe on 01 June 2015 of a British “Challenger 2” tank after it rolled over a car's front in Lippe, Germany, 01 June 2015. Police reported that a 18-year old female driving beginner from Detmold apparently overlooked a convoy of tanks when she turned left onto the Panzeringstrasse (lit. Tank Ring Road). (Photo by EPA/Polizei Lippe)

Members of the Chinese military orchestra march past a screen showing the Chinese Communist flag on Tiananmen Square before a celebration marking the 100th founding anniversary of the Chinese Communist Party, in Beijing, China, 01 July 2021. China celebrates on 01 July the 100th anniversary of the founding of the ruling Chinese Communist Party. (Photo by Roman Pilipey/EPA/EFE)

Protesters march against the death in Minneapolis police custody of George Floyd, in the Manhattan borough of New York City, U.S., June 1, 2020. (Photo by Mike Segar/Reuters)