Grinders are on display for sale during the HempCon 2011 Medical Marijuana Expo at the Los Angeles Convention Center on August 26, 2011 in Los Angeles, California. The three-day event includes exhibits, evaluation services, legal services, equipment, and accessories. (Photo by Kevork Djansezian/Getty Images)

English pop singer Shane Fenton, later known as Alvin Stardust, autographing a woman's leg in his dressing room. (Photo by John Pratt/Keystone Features/Getty Images). September 1962

Family Donation by Si Thu Ye Myint (Myanmar, Winner). Myin Twin village in upper Myanmar. (Photo by Si Thu Ye Myint/Sony World Photography)

Fireworks explode above St. Basil's cathedral during a rehearsal for the “Spasskaya Tower” international military music festival at Moscow's Red Square, September 4, 2015. Military bands from different countries will participate in the annual tattoo starting on Sunday. (Photo by Maxim Zmeyev/Reuters)

Savita, a street performer, helps her dog to balance on empty tin containers as they perform at a roadside in Ahmedabad September 7, 2014. (Photo by Amit Dave/Reuters)

Workers attempt to bring a tranquillised black rhino to the ground before dehorning in an effort to deter the poaching of one of the world's endangered species, at a farm outside Klerksdorp, in the north west province, South Africa, February 24, 2016. (Photo by Siphiwe Sibeko/Reuters)

A group of policemen and passers-by survey the wreckage of a taxi in Stoke Newington, London. Its front wheel lies on the pavement next to a sign bearing the ironic instruction “All Cars Stop Here”. 14th February 1930. (Photo by Fox Photos). P.S. All pictures are presented in high resolution.

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)